molbox1+™/molbox1+S

molbloc® Terminal(Ver. 6.00 and Higher)
Operation and Maintenance Manual© 2010 Fluke Calibration Warning
High pressure liquids and gases are potentially hazardous. Energy stored in theseliquids and gases can be released unexpectedly and with extreme force. Highpressure systems should be assembled and operated only by personnel who havebeen instructed in proper safety practices.

© 2010 Fluke Calibration All rights reserved.
Information in this document is subject to change without notice. No part of this document may be reproduced or transmitted in any
form or by any means, electronic or mechanical, for any purpose, without the express written permission of Fluke Calibration, 4765
East Beautiful Lane, Phoenix, Arizona 85044-5318 USA.
Fluke Calibration makes sincere efforts to ensure the accuracy and quality of its published materials; however, no warranty,
expressed or implied, is provided. Fluke Calibration disclaims any responsibility or liability for any direct or indirect damages
resulting from the use of the information in this manual or products described in it. Mention of any product or brand does notconstitute an endorsement by Fluke Calibration of that product or brand. This manual was originally composed in English and was
subsequently translated into other languages. The fidelity of the translation cannot be guaranteed. In case of conflict between the
English version and other language versions, the English version predominates.
Fluke Calibration, FCAL, DH, DHI, molbox1, molbox1+, molbloc, molbloc-L, molbloc-S, molstic, COMPASS, CalTool aretrademarks, registered and otherwise, of Fluke Corporation.
VCR is a registered trademark of the Swagelok Company.
Viton is a registered trademarks of DuPont deNemours Company.
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Document No. 3540962
100927
Printed in the USA.

© 2010 Fluke Calibration

Page IITable of Contents
Table of Contents ................................................................. III
Tables ................................................................................ VII
Figures .............................................................................. VIII
About This Manual ................................................................ IX
1.

Introduction ..................................................................... 1
1.1

Product Overview ................................................................................................................................... 1
1.1.1
1.1.1.1
1.1.1.2

1.2

Specifications ......................................................................................................................................... 3
1.2.1
1.2.2
1.2.3
1.2.4
1.2.5
1.2.5.1
1.2.5.2
1.2.6
1.2.6.1
1.2.6.2

2.

molbloc Flow Elements ........................................................................................................................... 2
molbloc-L Flow Element ......................................................................................................................... 2
molbloc-S Flow Element ......................................................................................................................... 3
General Specifications............................................................................................................................. 3
Reference Pressure Transducer (RPT) Specifications .......................................................................... 4
Temperature Measurement Specifications ............................................................................................. 4
MFC Control Function (Optional) Specifications ................................................................................... 5
Flow Measurement Specifications .......................................................................................................... 5molbloc-L ............................................................................................................................................... 5molbloc-S ............................................................................................................................................... 9
Front and Rear Panels ........................................................................................................................... 24
Front Panel .......................................................................................................................................... 24
Rear Panel ........................................................................................................................................... 24

Installation ..................................................................... 25
2.1

Unpacking and Inspection ................................................................................................................... 25
2.1.1
2.1.2

2.2
2.3

Site Requirements ................................................................................................................................ 25
Initial Setup ........................................................................................................................................... 26
2.3.1
2.3.2
2.3.3
2.3.4
2.3.5
2.3.6
2.3.7

2.4

Preparing for Operation ......................................................................................................................... 26
Power Connection .................................................................................................................................. 26
molbox1+ to molbloc Connections ....................................................................................................... 27
Gas Supply and Flowpath Connections ............................................................................................... 27
Vacuum Supply (molbloc-S only) .......................................................................................................... 28
Communications Connections .............................................................................................................. 28
MFC Control Option Connection ........................................................................................................... 29

Power UP and Verification ................................................................................................................... 29
2.4.1
2.4.2
2.4.3
2.4.4
2.4.5
2.4.6

2.5
2.6

Removing From Packaging ................................................................................................................... 25
Inspecting Contents ............................................................................................................................... 25

Power UP ................................................................................................................................................ 29
Check Proper Pressure Measurement Operation................................................................................. 29
Check Proper Temperature Measurement Operation .......................................................................... 29
Check the MFC Control Function (Optional) ........................................................................................ 30
Leak Check ............................................................................................................................................. 30
Check/Set Security Level ....................................................................................................................... 30

Additional Precautions to Take Before Making Flow Measurements .............................................. 30
Short Term Storage .............................................................................................................................. 31

Page III© 2010 Fluke Calibration

TABLE OF CONTENTS

3.

Operation ....................................................................... 33
3.1

General Operating Principles .............................................................................................................. 33
3.1.1
3.1.2
3.1.3
3.1.3.1
3.1.3.2
3.1.4
3.1.5

3.2

Main Run Screen .................................................................................................................................. 36
3.2.1
3.2.2

3.3

[K]............................................................................................................................................................ 41[GAS]....................................................................................................................................................... 42
molbloc-L Operation ............................................................................................................................. 43
molbloc-S Operation............................................................................................................................. 44[UNIT] ...................................................................................................................................................... 46
Mass Flow vs. Volume Flow ................................................................................................................. 47
Volumetrically Based Mass Flow Units ................................................................................................. 48
Volumetrically Based Mass Flow Units at Various Reference Temperatures (UXXX) ........................... 49
Volume Flow Units (vlm)....................................................................................................................... 49
Customizing FLOW Units Available Under The UNIT Function ............................................................. 50[TARE]..................................................................................................................................................... 51<1Tare> ............................................................................................................................................... 52<2Purge> ............................................................................................................................................. 56<3Leak Check> .................................................................................................................................... 57<4AutoZ> ............................................................................................................................................. 64<5BPR> (molbloc-S Operation Only) .................................................................................................... 69[P&T] (Pressure and Temperature) ....................................................................................................... 70
molbloc-L Operation ............................................................................................................................. 71
MOLBLOC-S operation ........................................................................................................................ 71[DISPLAY] ............................................................................................................................................... 72<1Rate> ............................................................................................................................................... 73<2Avg> (Average) ................................................................................................................................ 74<3 Hi/Lo> ............................................................................................................................................. 74<4Total> (Totalizer) .............................................................................................................................. 75<5Unit> ................................................................................................................................................ 77<6Deviation> ........................................................................................................................................ 78<7Freeze>............................................................................................................................................ 80<8Clean> ............................................................................................................................................. 80[A/B] ........................................................................................................................................................ 81[MFC](Optional) ...................................................................................................................................... 81
MFC Run Screens ................................................................................................................................ 82
MFC Profiles ........................................................................................................................................ 83
Units of Measure When Using the MFC Control Option ........................................................................ 83[RES] ....................................................................................................................................................... 84[SETUP] ................................................................................................................................................. 84
3.5.1
3.5.1.1
3.5.2
3.5.3
3.5.4
3.5.4.1
3.5.4.2
3.5.4.3
3.5.5
3.5.6
3.5.7
3.5.8
3.5.9

3.6

Keypad Layout and Protocol ................................................................................................................. 39
Direct Function Keys Summary ............................................................................................................ 40

Direct Function Keys............................................................................................................................ 41
3.4.1
3.4.2
3.4.2.1
3.4.2.2
3.4.3
3.4.3.1
3.4.3.2
3.4.3.3
3.4.3.4
3.4.3.5
3.4.4
3.4.4.1
3.4.4.2
3.4.4.3
3.4.4.4
3.4.4.5
3.4.5
3.4.5.1
3.4.5.2
3.4.6
3.4.6.1
3.4.6.2
3.4.6.3
3.4.6.4
3.4.6.5
3.4.6.6
3.4.6.7
3.4.6.8
3.4.7
3.4.8
3.4.8.1
3.4.8.2
3.4.8.3
3.4.9

3.5

molbloc-L Operation .............................................................................................................................. 37
molbloc-S Operation .............................................................................................................................. 38

Manual Operation ................................................................................................................................. 39
3.3.1
3.3.2

3.4

molbloc Channel A & Channel B ........................................................................................................... 33
molbloc-L and molbloc-S Operation ..................................................................................................... 33
Flow Ready/Not Ready Indication ......................................................................................................... 34
molbloc-L Operation ............................................................................................................................. 34
molbloc-S Operation............................................................................................................................. 34
Reference Pressure Transducer (RPT) Overpressure ......................................................................... 35
molbloc-S BPR Limits ............................................................................................................................ 35<1molbloc> ............................................................................................................................................. 85
molbloc-L and molbloc-S Size and Range Designations ....................................................................... 86<2stab> ................................................................................................................................................... 87<3ADJ> ................................................................................................................................................... 87<4A_B> ................................................................................................................................................... 88
General Operation (Aspects Common to Both A_B Modes) ................................................................. 89
A+B mode ............................................................................................................................................ 90
A/B Mode ............................................................................................................................................. 90<5MFC> ................................................................................................................................................... 91<6REG> ................................................................................................................................................... 92<7FLOWU>.............................................................................................................................................. 93<8PRESU> .............................................................................................................................................. 93<9TEMPU> .............................................................................................................................................. 94[SPECIAL] ............................................................................................................................................. 95
3.6.1
3.6.1.1
3.6.1.2
3.6.1.3© 2010 Fluke Calibration<1reset> .................................................................................................................................................. 95<1sets> ................................................................................................................................................ 96<2units> ............................................................................................................................................... 96<3MFC> ............................................................................................................................................... 97

Page IVTABLE OF CONTENTS

3.6.1.4
3.6.1.5
3.6.2
3.6.2.1
3.6.3
3.6.3.1
3.6.4
3.6.5
3.6.5.1
3.6.5.2
3.6.5.3
3.6.6
3.6.6.1
3.6.6.2
3.6.6.3
3.6.7
3.6.8
3.6.9

4.

Remote Operation ......................................................... 111
4.1
4.2

Overview ............................................................................................................................................. 111
Interfacing ........................................................................................................................................... 111
4.2.1
4.2.1.1
4.2.1.2
4.2.2

4.3

4.4

Command Syntax ..................................................................................................................................113
Command Summary .............................................................................................................................113
Error Messages .....................................................................................................................................115
Command Descriptions ........................................................................................................................116
IEEE Std. 488.2 Common and Status Commands ...............................................................................116
molbox1+ commands ..........................................................................................................................118

Status System ..................................................................................................................................... 138
4.4.1
4.4.1.1
4.4.1.2

Status Reporting System ......................................................................................................................138
Status Byte Register............................................................................................................................138
Standard Event Register .....................................................................................................................140

M a i n t e n a n c e , Ad j u s t m e n t s a n d C a l i b r a t i o n . . . . . . . . . . . . . . . . . . . . . . 1 4 1
5.1
5.2

Product Overview ............................................................................................................................... 141
Calibration Of Reference Pressure Transducers (RPTS) .................................................................... 142
5.2.1
5.2.1.1
5.2.2
5.2.3
5.2.4
5.2.4.1
5.2.4.2
5.2.5

5.3
5.4
5.5

OHMIC Measurement System Calibration/Adjustment Procedure .....................................................151

molbloc Flow Adjustment .................................................................................................................. 152
5.5.1

5.6
5.7
5.8

Principle.................................................................................................................................................142
PA and PM Coefficients ......................................................................................................................142
Equipment Required .............................................................................................................................143
Set-Up and Preparation ........................................................................................................................143
Viewing and Editing RPT Readings and Calibration Information.......................................................144
Viewing RPT outputs ...........................................................................................................................144
Viewing and Editing RPT PA, PM and Calibration Date ...........................................................................145
RPT Calibration/Adjustment Procedure Without Using CalTool for RPTs Software.........................146

MFC Control Function Adjustment ................................................................................................... 148
OHMIC Measurement [Temperature] System Verification .............................................................. 149
5.4.1

6.

RS232 Interface .....................................................................................................................................111
COM1 .................................................................................................................................................112
COM2 .................................................................................................................................................112
IEEE-488 (GPIB).....................................................................................................................................113

Commands .......................................................................................................................................... 113
4.3.1
4.3.2
4.3.3
4.3.4
4.3.4.1
4.3.4.2

5.

<4cal> .................................................................................................................................................. 97<5all> ................................................................................................................................................... 97<2level>................................................................................................................................................... 98
Security Levels ..................................................................................................................................... 98<3UL> .....................................................................................................................................................101
Upper Limit Alarm and Sequence ........................................................................................................102<4cal>.....................................................................................................................................................102<5Prefs>.................................................................................................................................................102<1ScrSVR> .........................................................................................................................................103<3ID> ..................................................................................................................................................103<3Time>..............................................................................................................................................104<6REMOTE> ..........................................................................................................................................104
COM1 and COM2 ...............................................................................................................................105
IEEE-488.............................................................................................................................................105
RS232 Self-Test ..................................................................................................................................105<7Drivers> .............................................................................................................................................106<8Head> .................................................................................................................................................106<9BPR> ..................................................................................................................................................107

molbloc Adjustment Procedure Without Using CalTool for molbloc Software .................................153

Reloading Embedded Software Into molbox1+
Flash Memory ............................................ 154
Reloading molbloc EEPROM File ...................................................................................................... 154
OVERHAUL ......................................................................................................................................... 154

Troubleshooting............................................................ 157
6.1

Overview ............................................................................................................................................. 157

Page V© 2010 Fluke Calibration

TABLE OF CONTENTS

7.

Appendix ...................................................................... 163
7.1

Conversion of Numerical Values ...................................................................................................... 163
7.1.1
7.1.2
7.1.3

7.2
7.3

Valve Drivers....................................................................................................................................... 166
MFC Control Function ........................................................................................................................ 168
7.3.1
7.3.1.1
7.3.1.2

7.4

8.

Pressure ................................................................................................................................................163
Temperature ..........................................................................................................................................163
Flow .......................................................................................................................................................164

MFC Connector .....................................................................................................................................168
Detailed Signal Descriptions................................................................................................................168
Popular Configurations ........................................................................................................................169

Limited Warranty and Limitation of Liability .................................................................................... 171

Glossary ...................................................................... 173© 2010 Fluke Calibration

Page VI

Tables
Table 1. molbloc-L Pressure Dependent Calibration Types ........................................................................ 7
Table 2. molbloc-L Ranges with Low Pressure and Downstream Calibrations ........................................... 7
Table 3: molbloc-L Ranges with High Pressure Calibrations...................................................................... 8
Table 4: molbloc-S Calibration Types ......................................................................................................... 11
Table 5: N2. molbloc-S Flow in Nitrogen at Various molbloc Upstream Pressures................................... 13
Table 6: Ar. molbloc-S Flow in Argon at Various molbloc Upstream Pressures........................................ 13
Table 7: He. molbloc-S Flow in Helium at Various molbloc Upstream Pressures ..................................... 14
Table 8: SF6. molbloc-S Flow in Sulfur Hexafluoride at Various molbloc Upstream Pressures ............... 14
Table 9: Xe. molbloc-S Flow in Xenon at Various molbloc Upstream Pressures ...................................... 15
Table 10: C4H10. molbloc-S Flow in Butane at Various molbloc Upstream Pressures ............................ 15
Table 11: C2H6. molbloc-S Flow in Ethane at Various molbloc Upstream Pressures .............................. 16
Table 12: C2H4. molbloc-S Flow in Ethylene at Various molbloc Upstream Pressures ........................... 16
Table 13: H2. molbloc-S Flow in Hydrogen at Various molbloc Upstream Pressures .............................. 17
Table 14: CH4. molbloc-S Flow in Methane at Various molbloc Upstream Pressures.............................. 17
Table 15: C3H8. molbloc-S Flow in Propane at Various molbloc Upstream Pressures ............................ 18
Table 16: CF4. molbloc-S Flow in Carbon Tetrafluoride at Various molbloc Upstream Pressures ........... 18
Table 17: C2F6. molbloc-S Flow in Hexafluoroethene at Various molbloc Upstream Pressures ............. 19
Table 18: CHF3. molbloc-S Flow in Trifluoromethane at Various molbloc Upstream Pressures .............. 19
Table 19: Air. molbloc-S Flow in Air at Various molbloc Upstream Pressures .......................................... 20
Table 20: CO2. molbloc-S Flow in Carbon Dioxide at Various molbloc Upstream Pressures .................. 20
Table 21: CO. molbloc-S Flow in Carbon Monoxide at Various molbloc Upstream Pressures ................. 21
Table 22: N2O. molbloc-S Flow in Nitrous Oxide at Various molbloc Upstream Pressures ..................... 21
Table 23: C4F8. molbloc-S Flow in Octafluorocyclobutane1 at Various molbloc Upstream Pressures .... 22
Table 24: O2. molbloc-S Flow in Oxygen at Various molbloc Upstream Pressures.................................. 22
Table 25: molbox1+ Parts List .................................................................................................................... 25
Table 26: Minimum molbloc-S Critical Flow (slm) in Nitrogen at Various molbloc-S Downstream
Pressures................................................................................................................................. 36
Table 27: Summary of molbox1+ Direct Function Key Operations ............................................................ 40
Table 28. Available molbloc-L Gases ........................................................................................................ 43
Table 29. Available Flow Units ................................................................................................................... 50
Table 30. Flow Units and Corresponding Total Mass or Volume Units ..................................................... 77
Table 31. molbloc-L Size and Nominal Range Designations ..................................................................... 86
Table 32. molbloc-S Size and Pressure to Flow Conversion Ratio (KF) .................................................... 86
Table 33. Pressure Units of Measure Available ......................................................................................... 94
Table 34. Security Levels - Functions NOT Executed Per Function/Level ................................................ 99
Table 35. COM1 and COM2 Available Settings....................................................................................... 105
Table 36. COM1 DB-9F Pin Designation ................................................................................................. 112
Table 37. COM2 DB-9M Pin Designation ................................................................................................ 112
Table 38. Command Summary ................................................................................................................ 113
Table 39. Error Messages ........................................................................................................................ 115
Table 40. Status Byte Register ................................................................................................................ 138
Table 41. Standard Event Register .......................................................................................................... 140
Table 42. Troubleshooting Checklist........................................................................................................ 157
Table 43. Pressure Unit Conversions ...................................................................................................... 163
Table 44. Temperature Unit Conversion .................................................................................................. 163

Page VII© 2010 Fluke Calibration

TABLES AND FIGURES

Table 45. Conversions from kg/s to sccm at 0 °C for Various Gases ...................................................... 164
Table 46. Conversions from sccm at 0 °C to Other Volumetrically Based Flow Units............................. 164
Table 47. Conversions from Volumetrically Based Flow Units at 0 °C to
Corresponding Units at Another Temperature (uxxx)............................................................ 165
Table 48. Conversions from kg/s to mole/s for Various Gases................................................................ 165
Table 49. Conversion from mole/s to pccm ............................................................................................. 165
Table 50. Conversion from sccm at 0 °C to Volume Flow Units at Another Pressure and Temperature 166
Table 51. Driver/Max Current Per Output ................................................................................................ 166
Table 52. External Drivers........................................................................................................................ 167
Table 53. Interface Cable Building Instructions ....................................................................................... 168
Table 54. Common MFC Connector Pin Out ........................................................................................... 170
Table 55. Brooks MFC Connector Pin Out .............................................................................................. 170
Table 56. Fluke Calibration Authorized Service Providers ...................................................................... 172

FiguresFigure 1. molbloc-L Upstream End Flange with Integrated Filter ................................................................ 2
Figure 2. molbox1+ Front Panel................................................................................................................. 24
Figure 3. Rear Panel .................................................................................................................................. 24
Figure 4. molbox1+ Internal Pneumatic Schematic - CHANNEL A ACTIVE, molbloc-L OPERATION ..... 33
Figure 5. Keypad Layout ............................................................................................................................ 39
Figure 6. molbox1+ Internal Pneumatic Schematic – ................................................................................ 52
Figure 7. molbox1+ Internal Pneumatic Schematic –TARING CHANNEL A, molbloc-S OPERATION ..................................................................... 55
Figure 8. molbox1+ Internal Pneumatic Schematic – PURGING CHANNEL A ........................................ 56
Figure 9. molbox1+ Internal Pneumatic Schematic - LEAK CHECK molbox CHANNEL A....................... 59
Figure 10. molbox1+ Internal Pneumatic Schematic - SYSTEM LEAK CHECK CHECKING OFFSET AND STABILITY ................................................................................... 60
Figure 11. molbox1+ Internal Pneumatic Schematic - SYSTEM LEAK CHECK ON CHANNEL A CHECKING OFFSET AND STABILITY ................................................................................... 63
Figure 12. molbox1+ Internal Pneumatic Schematic – molbloc-S OPERATION,
CHANNEL A, BPR ON .......................................................................................................... 108
Figure 13. molbox1+ Internal Pneumatic Schematic – molbloc-S OPERATION,
CHANNEL A, BPR OFF ........................................................................................................ 108
Figure 14. Status Byte Register ............................................................................................................... 139
Figure 15. molbox1+ Internal Pneumatic Schematic - ............................................................................. 145
Figure 16. Cable Driver Ports .................................................................................................................. 167© 2010 Fluke Calibration

Page VIII

About This ManualThis manual provides the user with the information necessary to operate a molbox1+ and a molbox1+S
molbloc terminal with molbloc mass flow elements to make mass flow measurements. Unless statedotherwise, references to molbox1+ also include molbox1+S. It also includes a great deal of additional
information provided to help you optimize use of a molbloc/molbox1+ system and take full advantage ofits many features and functions.
Before using the manual, take a moment to familiarize yourself with the Table of Contents structure.
All first time molbox1+ users should read Section 1. Section 3.1 provides a comprehensive description ofgeneral molbox1+ operating principles. Section 4. is for remote operation from an external computer.
Section 5 provides maintenance and calibration information. Section 6 is a quick troubleshooting guide.
Use this section to troubleshoot unexpected molbox1+ behavior based on the symptoms of that behavior.
Cross references are used extensively to direct you towards additional information on a topic.
Cross references are generally in parentheses and give the reference’s section number. For example:(see Section 11).
Certain words and expressions have specific meaning as they pertain to molbox1+. The Glossary
Section is useful as a quick reference for exact definition of specific words and expressions as they areused in this manual.

Note
For those of you who “don’t read manuals”, go directly to section 2.3, initial setup,
to set up your molbox1+. Then go to section 2.4, power up and verification. This
will get you running quickly with minimal risk of causing damage to yourself or
your molbox1+. Then… when you have questions or start to wonder about all thegreat features you might be missing, get into the manual!

Manual Conventions
 Caution“Caution” is used in throughout the manual to identify conditions or actions that
could cause harm to the molbox1+ or to the devices that are connected to themolbox1+.

 Warning“Warning” is used in throughout the manual to identify actions that could pose ahazard to the user of the molbox1+.

Note“Note” is used throughout the manual to identify operating and applications advice
and additional explanations.
[ ] Indicates direct function keys (e.g., [RANGE]).
< > Indicates molbox1+ screen displays (e.g., <1yes>).

Page IX© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Notes© 2010 Fluke Calibration

Page X

1.

Introduction

1.1

Product Overview

molbox1+ and molbox1+S are support units for making gas flow measurements using molbloc mass flow
elements. Although the molbox1+ and the molbox1+S are separate products their functions andoperation are virtually identical. The key difference is that molbox1+S is designed for higher flows and it
only supports molbloc-S mass flow elements. A molbox1+ supports both molbloc-L and molbloc-S. Each
product reads calibration data from a molbloc EEPROM and measures molbloc upstream anddownstream pressure using built-in high precision Reference Pressure Transducers (RPTs). There areseveral RPT range specific models in the molbox1+ product line: molbox1+ A350K, molbox1+ A700K,
molbox1+S A1.4M and molbox1+S A2M.
An ohmic measurement system reads the resistance of the molbloc platinum resistance thermometersfrom which the molbloc temperature is calculated. Using the molbloc calibration data, measured
pressures and temperature and gas properties stored in memory, the flow rate of the gas flowing throughthe molbloc is calculated.
Internal molbox1+ valves support on-board PRESSURE TRANSDUCER TARING, molbloc-S BPR MODES,LEAK TESTING and SELF PROTECTION functions as well as a GAS PURGE routine. The molbox1+S
does not support PRESSURE TRANSDUCER TARING as it does not support molbloc-L operation and does
not include a bypass valve to connect the upstream and downstream RPTs.
molbox1+ provides a local user interface via a front panel key pad and display and includes advanced
on-board functions. Remote communication capability is supported with RS232 and IEEE-488 interfaces.
molbox1+ is equipped to handle molblocs on two separate channels. This allows easy switching between
two different molblocs as well as certain special dual channel functions. Internal valving switches themolbox1+ pressure transducers from one molbloc to the other as needed.
molbox1+ is intended for applications in which minimizing measurement uncertainty is the most important
requirement and/or integrated control of mass flow controllers (MFCs) is needed. A second model,
molbox RFM, is available for applications where a compact presentation and lower cost are the mostdominant requirements.
molbox1+ replaces the Fluke/DHI molbox1 product line. molbox1+ introduces several productimprovements over molbox1 including:•Support for Q-RPT pressure sensor technology to improve linearity and precision on pressure
measurements.

•

Improved gas property uncertainty using data from NIST Reference Fluid Thermodynamic andTransport Properties Database (REFPROP).

•

Support of expanded molbloc modelization and polynomial linearization data structure andcalculations.
This new molbloc data structure allows greatly improved flow measurement
performance across the supported operating pressure and flow/Reynolds number ranges. This newmodel makes the Premium calibration option and resulting specifications possible.

•

Support for “named” molbloc calibrations – allowing storage of multiple pressure-dependentcalibrations in each gas on a molbloc. Also provides for stated operating limits of pressure, flow andReynolds number to be stored on the molbloc so the molbox1+ can alert the user of operating
conditions that are outside of the calibrated parameters, avoiding out of tolerance measurements.

Page 1© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL•

Simplified internal pneumatic design.

For easy identification, new molbox1+ terminals are produced with serial numbers of 2000 and higher.
Older molbox1 terminals may be eligible for upgrade to molbox1+ hardware, software and specifications
by Fluke/DHI.

1.1.1

molbloc Flow Elements

Two different types of molblocs may be used with molbox1+; molbloc-L (laminar) andmolbloc-S (sonic). molbox1+ supports operation with new or upgraded molblocs that havethe updated data structure to take advantage of molbox1+ version 6.00 or later features, andalso supports operation with older molblocs that do not have a version 6.00 data format.
Premium calibrations and associated specifications are only an option for molblocs that havethe version 6.00 format.

1.1.1.1

molbloc-L Flow Element

molbloc-L is the original molbloc laminar flow element. molbloc-L covers thelower portion of the molbloc/molbox1+ system flow range. The key molbloc-L
measurement is the differential pressure across the element, which is roughly
proportional to the mass flow rate through it. molbloc-L elements are calibrated
to be used at an absolute pressure which remains nearly constant, while thedifferential pressure varies with flow rate. Different operating pressure options
and their effect on molbloc flow range are described in Section 1.2.5.1.1.
In addition to the new data structure and modelization methods that became
available for molblocs with the introduction of molbox1+, all molbloc-L elementsof range 1E1-L to 3E4-L produced or upgraded after the release of molbox1+ are
equipped standard with an upstream ¼” VCR flange, or flowpath connection, thathas an integrated sintered metal filter. This filter is intended to be a last defense
against particulate contamination of the molbloc-L internal flowpath which canaffect molbloc-L measurements. Every effort should still be made to supply clean
dry gas to the molbloc to ensure its measurement performance and long-term
stability. molblocs that have the integrated upstream filter are recognizable by
the visible filter element as shown below.

Figure 1. molbloc-L Upstream End Flange with Integrated Filter
New molbloc-L elements produced with molbox1+ calibration data structure,
premium calibration options, and integrated filter hardware can be identified byhaving a serial number of 6000 or higher. Most older molbloc-L elements are
eligible for upgrade to this hardware/version 6.00 format by Fluke/DHI.

© 2010 Fluke Calibration

Page 2

1. INTRODUCTION

1.1.1.2

molbloc-S Flow Element

molbloc-S elements use critical (sonic) flow venturi nozzle technology to measureflows which overlap with the ranges of molbloc-L and cover the higher end of themolbloc/molbox1+ system flow range. The mass flow rate through a molbloc-S
element is roughly proportional to the upstream absolute pressure when the flowis “choked”, so the molbloc-S operating pressure can vary widely as the mass
flow rate is changed throughout the flow range. The limits of molbloc-S operatingpressure and flow ranges are defined by the molbloc-S calibration type,described in Section 1.2.5.2.2.
New calibration data structure and premium calibration options for molbloc-S
were also introduced along with molbox1+. molbloc-S elements produced withthis support will have serial number of 4000 or higher. Older molbloc-S elements
are eligible for upgrade to version 6.00 format by Fluke/DHI.

1.2

Specifications
1.2.1

General Specifications
Power Requirements

85 to 264 VAC, 50 to 60 Hz, 22 VA max. consumption

Fuse

1A/250V, slow blow, 5x20mm, NSN: 5920008930491

Operating Temperature Range

15 to 35 °C

Storage Temperature Range- 20 to 70 °C

Vibration

Meets MIL-T-28800D

Weight6.8 kg (15 lb) max.

Dimensions
Microprocessor
Communication Ports
Reference Pressure
Transducers(RPTs)

32 cm W x 12 cm H x 30 cm D
(12.6 in. x 4.7 in. x 11.8 in.) approx.
Motorola 68302, 16 MHz
RS232 (COM1), RS232 (COM2), IEEE-488
molbox1+ A350K

2 x 300 kPa (44 psia) calibrated range
oscillating quartz crystal

molbox1+ A700K

2 x 600 kPa (87 psia) calibrated range
oscillating quartz crystal

molbox1+S A1.4M 1 x 1200 kPa (174 psia) calibrated range
oscillating quartz crystal, 1 x 300 psi silicon basedmolbox1+S A2M
Pressure Limits

Pressure Connections
Ohmic Measurement System

1 x 2000 kPa (290 psia) calibrated range
oscillating quartz crystal, 1 x 300 psi silicon basedmolbox1+ A350K
Maximum working pressure
Maximum pressure without damage

300 kPa absolute (44 psia)
350 kPa absolute (50 psia)

molbox1+ A700K
Maximum working pressure
Maximum pressure without damage

600 kPa absolute (87 psia)
700 kPa absolute (102 psia)

molbox1+S A1.4M
Maximum working pressure
Maximum pressure without damage

1200kPa absolute (174 psia)
1500 kPa absolute (218 psia)

molbox1+S A2M
Maximum working pressure
Maximum pressure without damage

2000 kPa absolute (290 psia)
2200 kPa absolute (319 psia)

Quick connectors equivalent to Swagelok® QM Series (M2-B200)
Resolution

0.004 Ω

Accuracy± 0.04 Ω

Accuracy of 100 and 110 Ω reference resistors ± 0.01 %Stability of 100 and 110 Ω reference resistors
Page 3± 0.005 % per 3 yrs© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Gases Supported

molbloc-L and molbloc-S
Nitrogen (N2), dry Air, humid Air (molbloc-S only) , Argon (Ar), Butane(Butn), Carbon Monoxide (CO), Helium (He), Oxygen (O2), Carbon
Dioxide (CO2), Carbon Tetrafluoride (CF4), Octofluorocyclobutane(C4F8), Ethane (C2H6), Ethylene (C2H4), Fluoroform (CHF3),
Hexafluoroethane (C2F6), Hydrogen (H2), Methane (CH4), Nitrous
Oxide (N2O), Propane (C3H8), Sulfur Hexafluoride (SF6), Xenon (Xe)Flow Ranges
Valve Driver Option
CE Conformance

1.2.2

See Section 1.2.5.
(8) 12 V outputs.
Each output can sink,500 mA at 12 V, max. 1 A total (see Section 7.2).
Available. Must be specified.

Reference Pressure Transducer (RPT) Specifications
Type
Calibrated Range

Oscillating quartz crystal with mechanical bellows
A350K 20 to 300 kPa absolute (2.9 to 44 psia)
A700K 20 to 600 kPa absolute (2.9 to 87 psia)
A1.4M 100 to 1200 kPa absolute (14.5 to 174 psia)
100 to 2000 kPa absolute (14.5 to 290 psia)

A2M
Resolution

A350K 0.4 Pa (0.00005 psi)
A700K 0.7 Pa (0.0001 psi)
A1.4M 1.4 Pa (0.0002 psi)
2 Pa (0.0003 psi)

A2M
Accuracy

A350K
1Absolute pressure
Differential
A700K
1
Absolute pressure
Differential± (0.01 % of reading or 0.003 % Q-RPT span,
whichever is greater)± (4.2 Pa (0.0006 psi) or 0.026 % ΔP,
whichever is greater)± (0.01 % of reading or 0.003 % Q-RPT span,
whichever is greater)± (8.4 Pa (0.0012 psi) or 0.032 % ΔP,
whichever is greater)

A1.4M
Oscillating Quartz Up (HI)1
± (0.01 % of reading or 0.003 % Q-RPT span,
Absolute pressure
whichever is greater)
Silicon based Down (LO)
Absolute pressure± 0.06 % of full scale (full scale as defined by
upstream transducer)
A2M
Oscillating Quartz Up (HI)1
Absolute pressure± (0.01 % of reading or 0.003 % Q-RPT span,
whichever is greater)
Silicon based Down (LO)
Absolute pressure± 0.06 % of full scale (full scale as defined by
upstream transducer)
1

With regular use of Autozero. Add 0.005 % of Q-RPT span for one
year without use of AutoZero.

1.2.3

Temperature Measurement Specifications

Specifications are for molbloc mounted Platinum Resistance Thermometers (PRT) combinedwith molbox1+ resistance measurement system and temperature calculation.
Range

0 to 40 °C

Accuracy± 0.05 °C

Resolution

0.01 °C

The molbox1+ internal resistance measurement system is automatically calibrated usingreference 100 and 110 Ω (± 0.01 %) resistors (see Section 5.4).

© 2010 Fluke Calibration

Page 4

1. INTRODUCTION

1.2.4

MFC Control Function (Optional) Specifications

Analog Output
Voltage Range

0 to 6.000 VDC

Voltage Accuracy± 0.1 % FS

Voltage Resolution

0.1 mVDC

Current Range

4.01 to 20 mA

Current Accuracy± 0.1 % FS

Current Resolution

0.4 µA

Analog Input
Voltage Range

0 to 5.000 VDC

Min/Max Measurable Voltage- 0.25/6.00 VDC

Voltage Accuracy± 0.1 % FS

Voltage Resolution

1 mVDC

Current Range

4 to 20 mA

Current Accuracy± 0.1 % FS

Current Resolution

0.4 µA

Valve Test Point
Range

1.2.5

+ 2 to + 15 VDC (in reference to - 15 VDC)

Accuracy± 0.25 % FS

Resolution

2.5 mVDC

Flow Measurement Specifications

molbox1+ measures the flow through molbloc flow elements. There are two different types ofmolblocs, molbloc-L (laminar) (see Section 1.1.1.1) and molbloc-S (sonic) (see Section
1.1.1.2). Flow measurement specifications, calibration types, ranges and dimensions aredetailed separately for each molbloc type in section 1.2.5.1 and 1.2.5.2. For both molbloc-Land molbloc-S elements, there are separate performance specifications given for thepremium and standard calibration types that are offered. All flow measurement uncertainties
are valid only for measurents in a gas for which the molbloc is calibrated, and within therange of pressures for which the calibration is specified.

1.2.5.1

molbloc-L

The flow range, useable operating pressure and absolute and differential
pressure associated with molbloc-L operation depend on the molbloc used andits pressure-dependent calibration options (see Section1.2.5.1.3).

1.2.5.1.1

Standard molbloc-L Calibrations

Measurement Update
Rate
Range
Resolution

1 second
0 to molbloc full scale depending on gas and molbloc pressure
dependent calibration type (see Section 1.2.5.1.3)
0.0015 % FS

Linearity± 0.05 % of reading from 10 to 100 % FS,± 0.005 % FS under 10 % FS

Repeatability± 0.05 % of reading from 10 to 100 % FS,± 0.005 % FS under 10 % FS

Precision1± 0.07 % of reading from 10 to 100 % FS,± 0.007 % FS under 10 % FS

Stability2(1 year)± 0.09 % of reading from 10 to 100 % FS,± 0.009 % FS under 10 % FS

Page 5© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Measurement
Uncertainty3(N2 and any molbox1+
supported gas for which
the molbloc in use iscalibrated)± 0.2 % of reading from 10 to 100 % FS,± 0.02 % FS under 10 % FS
1E5 molbloc± 0.5% of reading from 25 to 100 % FS,± 0.125 % FS under 25 % FS

1

Precision: Combined linearity, hysteresis, repeatability.

2

Stability: Maximum change in zero and span over specified time period for typical molbox1+ and molbloc used
under typical conditions. As stability can only be predicted, stability for a specific molbloc and molbox1+ shouldbe established from experience.

3

Measurement uncertainty (accuracy): Maximum deviation of the molbox1+ flow indication from the true value ofthe flow through the molbloc including precision, stability and Fluke calibration standard measurement
uncertainty.

1.2.5.1.2

Premium molbloc-L Calibrations

Measurement Update
Rate
Range
Resolution

1 second
0 to molbloc full scale depending on gas and molbloc pressure
dependent calibration type (see Section 1.2.5.1.2)
0.0015 % FS

Linearity± 0.05 % of reading from 10 to 100 % FS,± 0.005 % FS under 10 % FS

Repeatability± 0.05 % of reading from 10 to 100 % FS,± 0.005 % FS under 10 % FS

Precision1± 0.07 % of reading from 10 to 100 % FS,± 0.007 % FS under 10 % FS

Stability2(1 year)± 0.03 % of reading from 10 to 100 % FS,± 0.003 % FS under 10 % FS

Measurement
Uncertainty3(N2 and any molbox1+
supported gas for which
the molbloc in use iscalibrated)± 0.125 % of reading from 10 to 100 % FS,± 0.0125 % FS under 10 % FS

1E5 molbloc-L Premium calibration not available

1

Precision: Combined linearity, hysteresis, repeatability.

2

Stability: Maximum change in zero and span over specified time period for typical molbox1+ and molbloc used
under typical conditions. As stability can only be predicted, stability for a specific molbloc and molbox1+ shouldbe established from experience.

3

Measurement uncertainty (accuracy): Maximum deviation of the molbox1+ flow indication from the true value ofthe flow through the molbloc including precision, stability and Fluke calibration standard measurement
uncertainty.

1.2.5.1.3

molbloc-L Pressure Dependent Calibration Types
Note

See your molbloc’s Calibration Report to determine thecalibration type of the molbloc you are using.
Different pressure dependent calibration options for molbloc-L elements determine
the range of operating pressures over which a molbloc can be used within its
mass flow measurement specifications. The calibration option also affects themolbloc flow range and the differential pressure associated with the flow range.
Measurement uncertainty (accuracy) specifications for molbloc-L are valid only
for gases with which the molbloc has been calibrated. All molbloc-L elements
are calibrated for N2. Calibrations with other gases are optional. FLUKE
calibration capability is not maintained at all times for all gases on all molbloc
designations. Check for availability before ordering calibrations.
The molbloc-L pressure dependent calibration types are summarized in Table 1.
© 2010 Fluke Calibration

Page 6

1. INTRODUCTION

Table 1. molbloc-L Pressure Dependent Calibration Types
CALIBRATION TYPEOPERATING PRESSURE

1E5
MOLBLOCALL OTHER
MOLBLOCS

200 to 325 kPa absolute(29 to 48 psia)
upstream of molbloc

5 kPa(.725 psi)

50 kPa(7.5 psi)

325 to 525 kPa absolute(48 to 76 psia)
upstream of molbloc

Not available

50 kPa(7.5 psi)

12.5 kPa(1.8 psi)

80 kPa (12 psi)(CALIBRATION NAME)
Low pressure(LOP)
High pressure(HIP)

Downstream

Atmospheric pressure
downstream of molbloc. 85 to
105 kPa (12 to15 psia).

(DOWN)NOMINAL DIFFERENTIALPRESSURE AT MAX. FLOW

Note
Differential pressure values are nominal and may vary by up to
15 % with the actual molbloc used.

1.2.5.1.4

molbloc-L Ranges with Low Pressure andDownstream Calibrations

Table 2. molbloc-L Ranges with Low Pressure and Downstream Calibrations
molbloc-L SIZE AND FULL SCALE FLOW (sccm @ 0 ºC)

INERT

GASES

SIZE
1E1

SIZE
5E1

SIZE
1E2

SIZE
2E2

SIZE
5E2

SIZE
1E3

SIZE
5E3

SIZE
1E4

SIZE
3E4

SIZE
1E5
100,000

Nitrogen

N2

10

50

100

200

500

1,000

5,000

10,00030,000

Argon

Ar

10

50

100

200

500

1,000

5,000

10,00030,00080,000Helium

He

10

50

100

200

500

1,000

5,000

10,00030,000100,000

Sulfur Hexafluoride

SF6

10

50

100

200

500

1,000

2,000
500

6,000
1,000

6,000
4,000

-----

Xenon

XE

10

40

80

150

400

800

3,500
500

8,000

11,0003,000

30,00020,000

C4H1

20

100

130
30

270
50

670
140

2,300

2,200
1,400

7,000
3,000

-----

-----

ButaneOTHER

FLUOROCARBONSFLAMMABLE

0

Ethane

C2H6

20

100

200

400

1,000

2,000

6,000
1,000

18,0002,000

18,0006,000

60,00050,000Ethylene

C2H4

16

80

160

320

800

1 600

7,000
1,000

16,00020,0005,000

70,00040,000Hydrogen

H2

20

100

200

400

1,000

2,000

10,00020,00060,000200,000

Methane

CH4

16

80

160

320

800

1 600

8,000

16,00040,0005,000

120,000
40,000

Propane

C3H8

20

100

200

400

1,000

2,000

3,000
1,000

10,0002,000

10,000
7,000

-----

CarbonTetrafluoride

CF4

10

50

100

200

500

1,000

4,000
600

10,00012,0003,000

36,00025,000Hexafluorethene

C2F6

10

50

100

200

500

1,000

2,000
600

6,000
1,200

6,000
4,000

-----

Trifluoromethane

CHF3

10

50

100

200

500

1,000

4,000
600

10,00012,0004,000

38,00030,000

Air

Air

10

50

100

200

500

1,000

5,000

10,00030,000100,000

Carbon Dioxide

CO2

10

50

100

200

500

1,000

5,000

10,00020,0004,000

60,00030,000Carbon Monoxide

CO

10

50

100

200

500

1,000

5,000

10,00030,000100,000

Nitrous Oxide

N2O

10

50

100

200

500

1,000

5,000

10,00020,0004,000

60,00030,000

C4F8

15

60
9

65
17

130
34

330
85

1,100
175

1,050
840

3,400
1,700

---

---

O2

10

50

100

200

500

1,000

5,000

10,00030,00080,000Octafluorocyclobutane
Oxygen1

See Table 3 for footnotes.

Page 7© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

1.2.5.1.5

molbloc-L Ranges with High Pressure
Calibrations
Table 3: molbloc-L Ranges with High Pressure Calibrations
molbloc-L SIZE AND FULL SCALE FLOW (sccm @ 0 ºC)
SIZE
1E1

SIZE
5E1

SIZE
1E2

SIZE
2E2

SIZE
5E2

SIZE
1E3

SIZE
5E3

SIZE
1E4

SIZE
3E4

SIZE
1E5

N2

20

100

200

400

1,000

2,000

10,00020,00040,000
7,500

N/A

Argon

Ar

20

100

200

400

1,000

2,000

10,00017,00035,0006,000

N/A

Helium

He

20

100

200

400

1,000

2,000

10,00020,00065,000

N/A

Sulfur Hexafluoride

SF6

25

100
15

120
30

250
50

600
150

2,000
300

2,000
1,400

6,200
2,800

---

N/A

Xenon

XE

20

100

150

350

650

1,700

3,350
950

11,0001,900

11,0005,700

N/A

Butane

C4H10

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

Ethane

C2H6

40

200

350
50

700
100

1,800
200

4,000

6,000
2 300

20,0004,500

20,00013,000N/A

Ethylene

C2H4

40

200

350

700

2,000

4,000

7,000
2,000

22,0004,000

22,00012,700

N/A

Hydrogen

GASES

OTHER

FLUOROCARBONSFLAMMABLE

INERT

Nitrogen

H2

40

200

400

900

2,000

4,500

22,00045,000130,000

N/A

Methane

CH4

35

175

350

700

1,700

3,500

13,0002,000

33,00042,00012,000

N/A

Propane

C3H8

50

200
25

200
50

400
100

1,000
250

3,500
500

3,500
2,600

11,000
5,400

---

N/A

CarbonTetrafluoride

CF4

20

100

200

400

1,000

2,000

3,700
1,200

12,0002,400

12,0007,300

N/A

Hexafluorethene

C2F6

25

100
15

120
30

250
50

600
150

2,000
300

1,800
1,500

6,000
3,000

---

N/A

Trifluoromethane

CHF3

25

125

240
30

450
60

1,200
150

2,500

4,000
1,500

12,0003,000

12,000
8,800

N/A

Air

Air

20

100

200

400

1,000

2,000

10,00020,00040,0007,200

N/A

Carbon Dioxide

CO2

25

125

250

500

1,250

2,500

6,600
1,400

20,0002,500

20,0008,800

N/A

Carbon Monoxide

CO

20

100

200

400

1,000

2,000

10,00020,00040,0007,500

N/A

Nitrous Oxide

N2O

25

125

250

500

1,250

2,500

11,0001,500

20,0003,000

20,000
9,000

N/A

C4F8

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

N/A

O2

20

100

200

400

1,000

2,000

10,00020,00040,0006,500

N/A

Octafluorocyclobutane
Oxygen2

A bold value indicates that the maximum flow is limited by the maximum Reynolds number value of 1 200 which is reached
before the normal differential pressure range is reached. In that case, the second value gives the minimum flow for whichmeasurement uncertainty (accuracy) is equal to the nominal uncertainty specification. Divide the second value by 10 whenusing molbox RFM microrange option.
Where there is no value in the field (–), this indicates that the maximum Reynolds number is reached before the differential
pressure reaches 5 kPa (1 kPa in the case of the 1E5 molbloc), therefore calibration with that gas is not useful.
1
2

Due to low vapor pressure, only downstream calibration type is available.
The operating pressure range is greater than the vapor pressure value for this gas.

© 2010 Fluke Calibration

Page 8

1. INTRODUCTION

1.2.5.1.6

molbloc-L Dimensions
molbloc-L SIZES [mm(in.)]
5E3 AND LOWER

5E3 AND LOWER

A

58.50 (2.303)

A

58.50 (2.303)

B

16.00 (0.630)

B

16.00 (0.630)

C

32.00 (1.260) SQ

C

32.00 (1.260) SQ

D

68.84 (2.750)

D68.84 (2.750)

E

19.06 (0.750)

E

19.06 (0.750)

F

124.00 (4.881)

F

124.00 (4.881)

G

1/4 in. VCR M

G

1/4 in. VCR M

1.2.5.2

molbloc-S

The flow range and operating pressure associated with molbloc-S operation
depend on the molbloc and molbox used and the the molbloc calibration option
selected (see Section 1.2.5.2.3)

1.2.5.2.1

Standard molbloc-S Calibrations

Measurement Update Rate
Range
Resolution

1 second
Depends on molbloc-S pressure dependent calibration type(see Section 1.2.5.2.2)
0.0015 % of FS

Linearity± 0.05 % of reading

Repeatability± 0.05 % of reading1± 0.06 % of reading

Precision

Page 9© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Predicted Stability2(1 year)Measurement Uncertainty3
With SP molbloc-S
calibration± 0.05 % of reading
A350K± 0.2 % of reading from 50 to 200 kPa

A700K± 0.2 % of reading from 50 to 500 kPa

S A1.4M ± 0.2 % of reading from 100 to 500 kPa± 0.2 % of 100 kPa flow from 50 to 100 kPa
S A2M± 0.2 % of reading from 200 to 500 kPa± 0.2 % of 200 kPa flow from 50 to 200 kPa

Measurement Uncertainty3

A350K± 0.2 % of reading from 20 to 200 kPa

With LP molbloc-S calibration

A700K± 0.2 % of reading from 50 to 200 kPa± 0.2 % of 50 kPa flow from 20 to 50 kPa

Measurement Uncertainty3

A700K± 0.2 % of reading from 200 to 500 kPa

With HP molbloc-S
calibration

S A1.4M ± 0.2 % of reading from 200 kPa to 1.2 MPa
S A2M± 0.2 % of reading from 200 kPa to 2 MPa[1] Precision: Combined linearity, hysteresis, repeatability.
[2] Stability: Maximum change in zero and span over specified time period for typical molbox1+ and molbloc used
under typical conditions. As stability can only be predicted, stability for a specific molbloc and molbox1+ shouldbe established from experience.
[3] Measurement uncertainty (accuracy): Maximum deviation of the molbox1+ flow indication from the true value ofthe flow through the molbloc including precision, stability and FLUKE calibration standard measurement
uncertainty.

1.2.5.2.2

Premium molbloc-S Calibrations

Measurement Update
Rate
Range
Resolution

1 second
Depends on molbloc-S pressure dependent calibration type(see Section 1.2.5.2.2)
0.0015 % of FS

Linearity± 0.05 % of reading

Repeatability± 0.05 % of reading1± 0.06 % of reading2± 0.03 % of reading

Precision

Predicted Stability(1 year)Measurement
Uncertainty3
With SP molbloc-S
calibration

A350K± 0.125 % of reading from 50 to 200 kPa

A700K± 0.125 % of reading from 50 to 500 kPa

S A1.4M ± 0.125 % of reading from 100 to 500 kPa± 0.125 % of 100 kPa flow from 50 to 100 kPa
S A2M± 0.125 % of reading from 200 to 500 kPa± 0.125 % of 200 kPa flow from 50 to 200 kPa

A350K± 0.125 % of reading from 20 to 200 kPa

A700K± 0.125 % of reading from 50 to 200 kPa± 0.125 % of 50 kPa flow from 20 to 50 kPa

Measurement
Uncertainty3

A700K± 0.125 % of reading from 200 to 500 kPa

With HP molbloc-S
calibration

S A2M

Measurement
Uncertainty3
With LP molbloc-S
calibration

S A1.4M ± 0.125 % of reading from 200 kPa to 1.2 MPa± 0.125 % of reading from 200 kPa to 2 MPa[1] Precision: Combined linearity, hysteresis, repeatability.
[2] Stability: Maximum change in zero and span over specified time period for typical molbox1+ and molbloc used
under typical conditions. As stability can only be predicted, stability for a specific molbloc and molbox1+ shouldbe established from experience.
[3] Measurement uncertainty (accuracy): Maximum deviation of the molbox1+ flow indication from the true value ofthe flow through the molbloc including precision, stability and Fluke calibration standard measurement
uncertainty.

© 2010 Fluke Calibration

Page 10

1. INTRODUCTION

1.2.5.2.3

molbloc-S Pressure Dependent Calibration Types
Note

See your molbloc’s Calibration Report to determine thecalibration type of the molbloc you are using.
Measurement uncertainty (accuracy) specifications for molblocs are valid only forgases with which the molbloc has been calibrated. All molbloc-S elements arecalibrated in one standard gas, either air or N2, and may be calibrated in othergases. Calibrations with other gases are optional. The list of gases which canbe measured by molbloc-S is the same as molbloc-L. FLUKE calibration
capability is not maintained at all times for all gases on all molbloc designations.
Check for availability before ordering calibrations.
molbloc-S calibrations are performed over flow ranges corresponding to one ofthree pressure ranges, summarized in Table 15.
Table 4: molbloc-S Calibration Types
CALIBRATION TYPE(CALIBRATION NAME)
Low pressure(LP)Standard pressure(SP)
High pressure(HP)

OPERATING PRESSURE
20 to 200 kPa absolute(3 to 30 psia)
upstream of molbloc
50 to 500 kPa absolute(7 to 70 psia)
upstream of molbloc
200 to 2000 kPa absolute(29 to 290 psia)
upstream of molbloc

Note
molbloc-S flow measurements are valid only when the ratio ofpressure downstream to the pressure upstream of the nozzle is
low enough to assure a critical (choked) flow (see Section 3.1.5).

Page 11© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

1.2.5.2.4

molbloc-S Ranges

molbloc-S flow ranges are defined by the molbloc’s Pressure to Flow Conversion
Ratio, KF, the gas used, the absolute pressure that can be delivered upstream ofmolbloc-S, the downstream pressure and the acceptable back pressure ratio(see Section 3.1.5). KF is expressed in units of sccm/kPa and defines therelationship between mass flow in nitrogen and the absolute upstream pressuredelivered to the molbloc-S. molbloc-S sizes are defined by the nominal KF of themolbloc-S nozzle, using scientific notation, for example a 1E3 molbloc-S has a KF
of 1,000 sccm/kPa. To differentiate from molbloc-L size designations, thismolbloc size is designated 1E3-S.
The molbox1+ pressure range, the molbloc-S calibration type (see Section 1.2.5.2.2)
and the back pressure ratio (BPR) requirements limit the pressures, and flows,over which a molbloc-S can be used within known measurement uncertainty
limits. In practice, the usable range of a molbloc-S in a given application also may
depend on the available gas supply pressure, the presence and flow capacity of avacuum pump downstream or the allowable back pressure on an upstream DUT.
The mass flow range of a molbloc-S element is dependent on the properties of the gas
used, so the range of a molbloc-S is different for each supported gas. The flow ranges
for each molbloc-S size at various typical operating pressures are summarized
separately for each molbloc-S supported gas in the Tables below. For the common
application of using a molbloc-S with its downstream pressure at or near atmosphericpressure, it is helpful to know what minimum flow can be measured before violatingback pressure ratio requirements (see Section 3.1.5). In the tables below, thisminimum flow value is given in the “Minimum without vacuum” column.
FLUKE calibration capability may not be available for some of the gases listed,or may be limited to less than the maximum flow rate listed. Check for availability
before ordering calibrations.
The following notes apply to the range tables below:
Ratio = Inverse square root density ratio of the current gas to Nitrogen
KF = Pressure to Flow Conversion Ratio, sccm/kPa
To estimate a flow in a given gas at a given pressure: Flow(slm) = KF * Pressurein kPa absolute / 1000 * Gas Ratio© 2010 Fluke Calibration

Page 12

1. INTRODUCTION

Table 5: N2. molbloc-S Flow in Nitrogen at Various molbloc Upstream Pressures
Nitrogen
Ratio = 1

DESIGNATOR

1E1-S
2E1-S
5E1-S
1E2-S

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]N2
KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum (3)200 kPa(30 psia)

500 kPa(70 psia)

10

0.2

0.5

1

2.0

2

5

20
50
100

0.4

1

1

2.5

2

5

2
5
10

3.5
7.7
15

4
10
20

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

7

12

20

10

14

24

40

25

35

60

100

50

70

120

200

240

400

2E2-S

200

4

10

20

28

40

100

140

5E2-S

500

10

25

50

67

100

250

350

600

1,000

1E3-S

1,000

20

50

100

129

200

500

700

1,200

2,000

2E3-S

2,000

40

100

200

248

400

1,000

1,400

2,400

4,000

5E3-S

5,000

100

250

500

596

1,000

2500

3,500

6,000

10,000

1E4-S

10,000

200

500

1,000

1,173

2,000

5,000

7,000

12,00020,000[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Table 6: Ar. molbloc-S Flow in Argon at Various molbloc Upstream Pressures
Argon
Ratio = 0.837

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]Ar
KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum (3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.2

0.4

0.8

1.7

1.7

4.2

5.9

10.0

16.7

2E1-S

20

0.3

0.8

1.7

3.0

3.3

8.4

11.7

20.1

33.5

5E1-S

50

0.8

2.1

4.2

6.5

8.4

20.9

29.3

50.2

83.7

1E2-S

100

1.7

4.2

8.4

12.9

16.7

41.9

58.6

100.5

167.4

2E2-S

200

3.3

8.4

16.7

23.3

33.5

83.7

117.2

200.9

334.9

5E2-S

500

8.4

20.9

41.9

57.1

83.7

209.3

293.0

502.3

837.2

1E3-S

1,000

16.7

41.9

83.7

107.8

167.4

418.6

586.0

1,004.6

1,674.4

2E3-S

2,000

33.5

83.7

167.4

207.6

334.9

837.2

1,172.1

2,009.3

3,348.8

5E3-S

5,000

83.7

209.3

418.6

498.2

837.2

2,093.0

2,930.2

5,023.2

8,372.0

1E4-S

10,000

167.4

418.6

837.2

996.2

1,674.4

4,186.0

5,860.4

10,046.4

16,744.0

DESIGNATOR[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Page 13© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Table 7: He. molbloc-S Flow in Helium at Various molbloc Upstream Pressures
HeliumRatio = 2.647

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]He
KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum (3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.5

1.3

2.6

9.4

5.3

13.2

18.5

31.8

52.9

2E1-S

20

1.1

2.6

5.3

13.1

10.6

26.5

37.1

63.5

105.9

5E1-S

50

2.6

6.6

13.2

25.7

26.5

66.2

92.6

158.8

264.7

1E2-S

100

5.3

13.2

26.5

51.4

52.9

132.3

185.3

317.6

529.4

2E2-S

200

10.6

26.5

52.9

91.5

105.9

264.7

370.6

635.2

1,058.7

5E2-S

500

26.5

66.2

132.3

199.4

264.7

661.7

926.4

1,588.1

2,646.8

1E3-S

1000

52.9

132.3

264.7

398.7

529.4

1,323.4

1,852.8

3,176.2

5,293.6

2E3-S

2000

105.9

264.7

529.4

695.1

1,058.7

2,646.8

3,705.5

6,352.3 10,587.2

5E3-S

5000

264.7

661.7

1,323.4

1,737.8

2,646.8

6,617.0

9,263.8

15,880.9 26,468.1

1E4-S

10,000529.4

1,323.4

2,646.8

3,281.0

5,293.6

13,234.0

18,527.7

31,761.7 52,936.2

DESIGNATOR[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Table 8: SF6. molbloc-S Flow in Sulfur Hexafluoride at Various molbloc Upstream Pressures
Sulfur Hexafluoride
Ratio = 0.435

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]SF6

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.1

0.2

0.4

0.8

0.9

2.2

3.0

n/a

[4]

n/a

2E1-S

20

0.2

0.4

0.9

1.4

1.7

4.3

6.1

n/a

[4]

n/a

5E1-S

50

0.4

1.1

2.2

3.1

4.3

10.9

15.2

n/a

[4]

n/a

1E2-S

100

0.9

2.2

4.3

5.9

8.7

21.7

30.4

n/a

[4]

n/a

2E2-S

200

1.7

4.3

8.7

11.4

17.4

43.5

60.9

n/a

[4]

n/a

5E2-S

500

4.3

10.9

21.7

26.9

43.5

108.7

152.2

n/a

[4]

n/a

1E3-S

1,000

8.7

21.7

43.5

53.8

87.0

217.4

304.3

n/a

[4]

n/a

2E3-S

2,000

17.4

43.5

87.0

100.0

173.9

434.8

608.7

n/a

[4]

n/a

5E3-S

5,000

43.5

108.7

217.4

249.9

434.8

1,086.9

1,521.7

n/a

[4]

n/a

1E4-S

10,000

87.0

217.4

434.8

499.7

869.5

2,173.8

3,043.4

n/a

[4]

n/a

DESIGNATOR

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]

[4]

© 2010 Fluke Calibration

Page 14

[4]
[4]
[4]
[4]

[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.

[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

[4]
[4]

[1] Flow values in table are valid only when critical flow is established.

[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

[4]

[4]

1. INTRODUCTION

Table 9: Xe. molbloc-S Flow in Xenon at Various molbloc Upstream Pressures
Xenon
Ratio = 0.460

Xe

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.1

0.2

0.4

0.8

0.7

1.8

3.2

n/a

[4]

n/a

2E1-S

20

0.1

0.4

0.7

1.4

1.5

3.6

6.4

n/a

[4]

n/a

5E1-S

50

0.4

0.9

1.8

3.6

3.6

9.1

16.1

n/a

[4]

n/a

1E2-S

100

0.7

1.8

3.6

6.5

7.3

18.2

32.2

n/a

[4]

n/a

2E2-S

200

1.5

3.6

7.3

12.9

14.6

36.4

64.5

n/a

[4]

n/a

5E2-S

500

3.6

9.1

18.2

29.7

36.4

91.0

161.2

n/a

[4]

n/a

1E3-S

1,000

7.3

18.2

36.4

59.3

72.8

182.0

322.3

n/a

[4]

n/a

2E3-S

2,000

14.6

36.4

72.8

109.6

145.6

364.0

644.6

n/a

[4]

n/a

5E3-S

5,000

36.4

91.0

182.0

267.2

364.0

910.0

1,611.5

n/a

[4]

n/a

1E4-S

10,000

72.8

182.0

364.0

529.2

728.0

1,819.9

3,223.1

n/a

[4]

n/a

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Table 10: C4H10. molbloc-S Flow in Butane at Various molbloc Upstream Pressures
ButaneRatio = 0.680

C4H10

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

1E1-S

10

0.1

0.3

0.7

1.0

1.4

2E1-S

20

0.3

0.7

1.4

1.9

5E1-S

50

0.7

1.7

3.4

1E2-S

100

1.4

3.4

2E2-S

200

2.7

5E2-S

500

1E3-S

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]500 kPa(70 psia)

700 kPa(100 psia)

n/a

[4]

n/a

2.7

n/a

[4]

n/a

4.8

6.8

n/a

[4]

n/a

6.8

9.0

13.6

n/a

[4]

n/a

6.8

13.6

18.0

27.2

n/a

[4]

n/a

6.8

17.0

34.0

42.2

68.0

n/a

[4]

n/a

1,000

13.6

34.0

68.0

84.4

136.0

n/a

[4]

n/a

2E3-S

2,000

27.2

68.0

136.0

157.0

272.0

n/a

[4]

n/a

5E3-S

5,000

68.0

170.0

340.0

392.4

679.9

n/a

[4]

n/a

1E4-S

10,000

136.0

340.0

679.9

784.9

1,359.8

n/a

[4]

n/a

1.2 MPa(174 psia)

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

2 MPa
(290 psia)

[4]

n/a

[4]

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Page 15© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Table 11: C2H6. molbloc-S Flow in Ethane at Various molbloc Upstream Pressures
EthaneRatio = 0.960

C2H6

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.2

0.5

1.0

1.5

1.9

4.8

6.7

n/a

[4]

n/a

2E1-S

20

0.4

1.0

1.9

3.0

3.8

9.6

13.4

n/a

[4]

n/a

5E1-S

50

1.0

2.4

4.8

6.7

9.6

24.0

33.6

n/a

[4]

n/a

1E2-S

100

1.9

4.8

9.6

13.4

19.2

48.0

67.2

n/a

[4]

n/a

2E2-S

200

3.8

9.6

19.2

25.2

38.4

96.0

134.5

n/a

[4]

n/a

5E2-S

500

9.6

24.0

48.0

61.9

96.0

240.1

336.1

n/a

[4]

n/a

1E3-S

1,000

19.2

48.0

96.0

118.7

192.1

480.2

672.3

n/a

[4]

n/a

2E3-S

2,000

38.4

96.0

192.1

228.6

384.2

960.4

1,344.6

n/a

[4]

n/a

5E3-S

5,000

96.0

240.1

480.2

551.9

960.4

2,401.0

3,361.4

n/a

[4]

n/a

1E4-S

10,000

192.1

480.2

960.4

1,103.8

1,920.8

4,802.0

6,722.8

n/a

[4]

n/a

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Table 12: C2H4. molbloc-S Flow in Ethylene at Various molbloc Upstream Pressures
Ethylene
Ratio = 0.996

C2H4

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.2

0.5

1.0

1.7

2.0

5.0

7.0

n/a

[4]

n/a

2E1-S

20

0.4

1.0

2.0

3.1

4.0

10.0

13.9

n/a

[4]

n/a

5E1-S

50

1.0

2.5

5.0

7.5

10.0

24.9

34.9

n/a

[4]

n/a

1E2-S

100

2.0

5.0

10.0

13.9

19.9

49.8

69.7

n/a

[4]

n/a

2E2-S

200

4.0

10.0

19.9

27.7

39.8

99.6

139.4

n/a

[4]

n/a

5E2-S

500

10.0

24.9

49.8

64.2

99.6

248.9

348.5

n/a

[4]

n/a

1E3-S

1,000

19.9

49.8

99.6

128.2

199.2

497.9

697.0

n/a

[4]

n/a

2E3-S

2,000

39.8

99.6

199.2

237.0

398.3

995.8

1394.1

n/a

[4]

n/a

5E3-S

5,000

99.6

248.9

497.9

572.2

995.8

2,489.5

3485.2

n/a

[4]

n/a

1E4-S

10,000

199.2

497.9

995.8

1,144.4

1,991.6

4,978.9

6970.5

n/a

[4]

n/a

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]

[4]

© 2010 Fluke Calibration

Page 16

[4]
[4]
[4]
[4]

[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.

[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

[4]
[4]

[1] Flow values in table are valid only when critical flow is established.

[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

[4]

[4]

1. INTRODUCTION

Table 13: H2. molbloc-S Flow in Hydrogen at Various molbloc Upstream Pressures
Hydrogen
Ratio = 3.730

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

H2
KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum (3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.7

1.9

3.7

8.3

7.5

18.6

26.1

44.8

74.6

2E1-S

20

1.5

3.7

7.5

14.5

14.9

37.3

52.2

89.5

149.2

5E1-S

50

3.7

9.3

18.6

36.2

37.3

93.2

130.5

223.8

373.0

1E2-S

100

7.5

18.6

37.3

62.5

74.6

186.5

261.1

447.6

746.0

2E2-S

200

14.9

37.3

74.6

114.5

149.2

373.0

522.2

895.2

1,491.9

5E2-S

500

37.3

93.2

186.5

280.9

373.0

932.4

1,305.4

2,237.9

3,729.8

1E3-S

1,000

74.6

186.5

373.0

508.7

746.0

1,864.9

2,610.9

4,475.8

7,459.6

2E3-S

2,000

149.2

373.0

746.0

979.6

1,491.9

3,729.8

5,221.7

8,951.5

14,919.2

5E3-S

5,000

373.0

932.4

1,864.9

2,311.7

3,729.8

9,324.5

13,054.3

22,378.8

37,297.9

1E4-S

10,000746.0

1,864.9

3,729.8

4,623.4

7,459.6

18,649.0

26,108.6

44,757.5

74,595.9

DESIGNATOR[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Table 14: CH4. molbloc-S Flow in Methane at Various molbloc Upstream Pressures
MethaneRatio = 1.320

CH4

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.3

0.7

1.3

2.6

2.6

6.6

9.2

15.8

26.4

2E1-S

20

0.5

1.3

2.6

4.4

5.3

13.2

18.5

31.7

52.8

5E1-S

50

1.3

3.3

6.6

10.2

13.2

33.0

46.2

79.2

132.0

1E2-S

100

2.6

6.6

13.2

20.1

26.4

66.0

92.4

158.4

264.0

2E2-S

200

5.3

13.2

26.4

36.7

52.8

132.0

184.8

316.8

528.1

5E2-S

500

13.2

33.0

66.0

88.2

132.0

330.0

462.1

792.1

1,320.2

1E3-S

1,000

26.4

66.0

132.0

170.0

264.0

660.1

924.1

1,584.2

2,640.3

2E3-S

2,000

52.8

132.0

264.0

327.3

528.1

1,320.2

1,848.2

3,168.4

5,280.6

5E3-S

5,000

132.0

330.0

660.1

785.5

1,320.2

3,300.4

4,620.5

7,920.9

13,201.5

1E4-S

10,000

264.0

660.1

1,320.2

1,517.2

2,640.3

6,600.8

9,241.1

15,841.8

26,403.0

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2][1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Page 17© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Table 15: C3H8. molbloc-S Flow in Propane at Various molbloc Upstream Pressures
PropaneRatio = 0.789

C3H8

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.2

0.4

0.8

1.3

1.6

3.9

5.5

n/a

[4]

n/a

2E1-S

20

0.3

0.8

1.6

2.3

3.2

7.9

11.0

n/a

[4]

n/a

5E1-S

50

0.8

2.0

3.9

5.5

7.9

19.7

27.6

n/a

[4]

n/a

1E2-S

100

1.6

3.9

7.9

10.5

15.8

39.4

55.2

n/a

[4]

n/a

2E2-S

200

3.2

7.9

15.8

20.8

31.5

78.9

110.4

n/a

[4]

n/a

5E2-S

500

7.9

19.7

39.4

48.8

78.9

197.2

276.1

n/a

[4]

n/a

1E3-S

1,000

15.8

39.4

78.9

97.5

157.7

394.4

552.1

n/a

[4]

n/a

2E3-S

2,000

31.5

78.9

157.7

181.4

315.5

788.7

1,104.2

n/a

[4]

n/a

5E3-S

5,000

78.9

197.2

394.4

453.2

788.7

1,971.8

2,760.5

n/a

[4]

n/a

1E4-S

10,000

157.7

394.4

788.7

906.5

1,577.4

3,943.6

5,521.0

n/a

[4]

n/a

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Table 16: CF4. molbloc-S Flow in Carbon Tetrafluoride at Various molbloc Upstream Pressures
Carbon Tetrafluoride
Ratio = 0.563

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

CF4KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.1

0.3

0.6

0.9

1.1

2.8

3.9

n/a

[4]

n/a

2E1-S

20

0.2

0.6

1.1

1.8

2.3

5.6

7.9

n/a

[4]

n/a

5E1-S

50

0.6

1.4

2.8

4.1

5.6

14.1

19.7

n/a

[4]

n/a

1E2-S

100

1.1

2.8

5.6

7.9

11.3

28.1

39.4

n/a

[4]

n/a

2E2-S

200

2.3

5.6

11.3

15.7

22.5

56.3

78.8

n/a

[4]

n/a

5E2-S

500

5.6

14.1

28.1

36.3

56.3

140.7

197.0

n/a

[4]

n/a

1E3-S

1,000

11.3

28.1

56.3

69.9

112.6

281.4

394.0

n/a

[4]

n/a

2E3-S

2,000

22.5

56.3

112.6

134.1

225.1

562.9

788.0

n/a

[4]

n/a

5E3-S

5,000

56.3

140.7

281.4

323.4

562.9

1,407.2

1,970.0

n/a

[4]

n/a

1E4-S

10,000

112.6

281.4

562.9

646.9

1,125.7

2,814.3

3,940.1

n/a

[4]

n/a

DESIGNATOR

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]

[4]

© 2010 Fluke Calibration

Page 18

[4]
[4]
[4]
[4]

[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.

[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

[4]
[4]

[1] Flow values in table are valid only when critical flow is established.

[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

[4]

[4]

1. INTRODUCTION

Table 17: C2F6. molbloc-S Flow in Hexafluoroethene at Various molbloc Upstream Pressures
Hexafluoroethene
Ratio = 0.447

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

C2F6

KF
[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.1

0.2

0.4

0.8

0.9

2.2

3.1

n/a

[4]

n/a

2E1-S

20

0.2

0.4

0.9

1.3

1.8

4.5

6.3

n/a

[4]

n/a

5E1-S

50

0.4

1.1

2.2

3.2

4.5

11.2

15.7

n/a

[4]

n/a

1E2-S

100

0.9

2.2

4.5

5.9

8.9

22.4

31.3

n/a

[4]

n/a

2E2-S

200

1.8

4.5

8.9

11.8

17.9

44.7

62.6

n/a

[4]

n/a

5E2-S

500

4.5

11.2

22.4

27.6

44.7

111.8

156.6

n/a

[4]

n/a

1E3-S

1,000

8.9

22.4

44.7

55.3

89.5

223.7

313.1

n/a

[4]

n/a

2E3-S

2,000

17.9

44.7

89.5

102.9

178.9

447.3

626.3

n/a

[4]

n/a

5E3-S

5,000

44.7

111.8

223.7

257.1

447.3

1,118.3

1,565.7

n/a

[4]

n/a

1E4-S

10,000

89.5

223.7

447.3

514.1

894.7

2,236.7

3,131.3

n/a

[4]

n/a

DESIGNATOR

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Table 18: CHF3. molbloc-S Flow in Trifluoromethane at Various molbloc Upstream Pressures
Trifluoromethane
Ratio = 0.629

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

CHF3

KF
[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.1

0.3

0.6

1.0

1.3

3.1

4.4

n/a

[4]

n/a

2E1-S

20

0.3

0.6

1.3

2.0

2.5

6.3

8.8

n/a

[4]

n/a

5E1-S

50

0.6

1.6

3.1

4.4

6.3

15.7

22.0

n/a

[4]

n/a

1E2-S

100

1.3

3.1

6.3

8.8

12.6

31.5

44.1

n/a

[4]

n/a

2E2-S

200

2.5

6.3

12.6

17.2

25.2

62.9

88.1

n/a

[4]

n/a

5E2-S

500

6.3

15.7

31.5

40.6

62.9

157.3

220.3

n/a

[4]

n/a

1E3-S

1,000

12.6

31.5

62.9

77.9

125.9

314.7

440.6

n/a

[4]

n/a

2E3-S

2,000

25.2

62.9

125.9

149.9

251.8

629.4

881.1

n/a

[4]

n/a

5E3-S

5,000

62.9

157.3

314.7

361.7

629.4

1,573.4

2202.8

n/a

[4]

n/a

1E4-S

10,000

125.9

314.7

629.4

723.3

1,258.8

3,146.94405.6

n/a

[4]

n/a

DESIGNATOR

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Page 19© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Table 19: Air. molbloc-S Flow in Air at Various molbloc Upstream Pressures
Air
Ratio = 0.983

Air

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.2

0.5

1.0

2.0

2.0

4.9

6.9

11.8

19.7

2E1-S

20

0.4

1.0

2.0

3.4

3.9

9.8

13.8

23.6

39.3

5E1-S

50

1.0

2.5

4.9

7.6

9.8

24.6

34.4

59.0

98.3

1E2-S

100

2.0

4.9

9.8

15.2

19.7

49.2

68.8

118.0

196.7

2E2-S

200

3.9

9.8

19.7

27.4

39.3

98.3

137.7

236.0

393.4

5E2-S

500

9.8

24.6

49.2

67.1

98.3

245.9

344.2

590.1

983.5

1E3-S

1,000

19.7

49.2

98.3

126.7

196.7

491.7

688.4

1,180.2

1,967.0

2E3-S

2,000

39.3

98.3

196.7

243.9

393.4

983.5

1,376.9

2,360.4

3,933.9

5E3-S

5,000

98.3

245.9

491.7

585.2

983.5

2,458.7

3,442.2

5,900.9

9,834.8

1E4-S

10,000

196.7

491.7

983.5

1,170.3

1,967.0

4,917.4

6,884.4

11,801.8

19,669.7

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2][1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Table 20: CO2. molbloc-S Flow in Carbon Dioxide at Various molbloc Upstream Pressures
Carbon Dioxide
Ratio = 0.795

CO2

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.2

0.4

0.8

1.4

1.6

4.0

5.6

n/a

[4]

n/a

2E1-S

20

0.3

0.8

1.6

2.5

3.2

8.0

11.1

n/a

[4]

n/a

5E1-S

50

0.8

2.0

4.0

6.2

8.0

19.9

27.8

n/a

[4]

n/a

1E2-S

100

1.6

4.0

8.0

11.1

15.9

39.8

55.7

n/a

[4]

n/a

2E2-S

200

3.2

8.0

15.9

22.1

31.8

79.5

111.3

n/a

[4]

n/a

5E2-S

500

8.0

19.9

39.8

51.2

79.5

198.8

278.4

n/a

[4]

n/a

1E3-S

1,000

15.9

39.8

79.5

102.4

159.1

397.7

556.7

n/a

[4]

n/a

2E3-S

2,000

31.8

79.5

159.1

189.3

318.1

795.3

1,113.4

n/a

[4]

n/a

5E3-S

5,000

79.5

198.8

397.7

473.2

795.3

1,988.3

2,783.6

n/a

[4]

n/a

1E4-S

10,000

159.1

397.7

795.3

914.1

1,590.6

3,976.6

5,567.2

n/a

[4]

n/a

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]

[4]

© 2010 Fluke Calibration

Page 20

[4]
[4]
[4]
[4]

[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.

[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

[4]
[4]

[1] Flow values in table are valid only when critical flow is established.

[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

[4]

[4]

1. INTRODUCTION

Table 21: CO. molbloc-S Flow in Carbon Monoxide at Various molbloc Upstream Pressures
Carbon Monoxide
Ratio = 1.000

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]COKF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.2

0.5

1.0

2.0

2.0

5.0

7.0

12.0

20.0

2E1-S

20

0.4

1.0

2.0

3.5

4.0

10.0

14.0

24.0

40.0

5E1-S

50

1.0

2.5

5.0

7.7

10.0

25.0

35.0

60.0

100.0

1E2-S

100

2.0

5.0

10.0

15.4

20.0

50.0

70.0

120.0

200.0

2E2-S

200

4.0

10.0

20.0

27.8

40.0

100.0

140.0

240.0

400.0

5E2-S

500

10.0

25.0

50.0

68.3

100.0

250.0

350.0

600.0

1,000.0

1E3-S

1,000

20.0

50.0

100.0

128.7

200.0

500.0

700.0

1,200.0

1,999.9

2E3-S

2,000

40.0

100.0

200.0

247.9

400.0

1,000.0

1,399.9

2,399.9

3,999.9

5E3-S

5,000

100.0

250.0

500.0

595.0

1,000.0

2,499.9

3,499.9

5,999.8

9,999.6

1E4-S

10,000

200.0

500.0

1,000.0

1,190.0

1,999.9

4,999.8

6,999.7

11,999.6

19,999.3

DESIGNATOR[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

Table 22: N2O. molbloc-S Flow in Nitrous Oxide at Various molbloc Upstream Pressures
Nitrous Oxide
Ratio = 0.795

N20

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1E1-S

10

0.2

0.4

0.8

1.4

1.6

4.0

5.6

n/a

[4]

n/a

2E1-S

20

0.3

0.8

1.6

2.5

3.2

8.0

11.1

n/a

[4]

n/a

5E1-S

50

0.8

2.0

4.0

6.2

8.0

19.9

27.8

n/a

[4]

n/a

1E2-S

100

1.6

4.0

8.0

11.1

15.9

39.8

55.7

n/a

[4]

n/a

2E2-S

200

3.2

8.0

15.9

22.1

31.8

79.5

111.3

n/a

[4]

n/a

5E2-S

500

8.0

19.9

39.8

51.2

79.5

198.8

278.3

n/a

[4]

n/a

1E3-S

1,000

15.9

39.8

79.5

102.4

159.0

397.6

556.6

n/a

[4]

n/a

2E3-S

2,000

31.8

79.5

159.0

189.3

318.0

795.1

1,113.2

n/a

[4]

n/a

5E3-S

5,000

79.5

198.8

397.6

473.1

795.1

1,987.8

2,782.9

n/a

[4]

n/a

1E4-S

10,000

159.0

397.6

795.1

913.7

1,590.2

3,975.6

5,565.8

n/a

[4]

n/a

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

1.2 MPa(174 psia)

2 MPa(290 psia)
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Page 21© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Table 23: C4F8. molbloc-S Flow in Octafluorocyclobutane1 at Various molbloc Upstream Pressures
Octafluorocyclobutane1
Ratio = 0.367
C4F8

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2]

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

1E1-S

10

0.1

0.2

0.4

0.6

0.7

2E1-S

20

0.1

0.4

0.7

1.1

5E1-S

50

0.4

0.9

1.8

1E2-S

100

0.7

1.8

2E2-S

200

1.5

5E2-S

500

1E3-S

500 kPa(70 psia)

700 kPa(100 psia)

n/a

[4]

n/a

1.5

n/a

[4]

n/a

2.4

3.7

n/a

[4]

n/a

3.7

4.8

7.3

n/a

[4]

n/a

3.7

7.3

9.2

14.7

n/a

[4]

n/a

3.7

9.2

18.3

22.7

36.7

n/a

[4]

n/a

1,000

7.3

18.3

36.7

43.8

73.3

n/a

[4]

n/a

2E3-S

2,000

14.7

36.7

73.3

84.3

146.7

n/a

[4]

n/a

5E3-S

5,000

36.7

91.7

183.3

210.7

366.7

n/a

[4]

n/a

1E4-S

10,000

73.3

183.3

366.7

421.4

733.3

n/a

[4]

n/a

DESIGNATOR

1.2 MPa(174 psia)

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

2 MPa
(290 psia)

[4]

n/a

[4]

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]

n/a

[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]
[4]

[1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).
[4] Operation in this gas is limited to lower pressures due to the gas vapor pressure.

Table 24: O2. molbloc-S Flow in Oxygen at Various molbloc Upstream Pressures
OxygenRatio = 0.935

O2

DESIGNATOR

KF[sccm/ kPa]

20 kPa(3 psia)

50 kPa(7 psia)

100 kPa(15 psia)

Minimum
without
vacuum(3)200 kPa(30 psia)

500 kPa(70 psia)

700 kPa(100 psia)

1.2 MPa(174 psia)

2 MPa(290 psia)

1E1-S

10

0.2

0.5

0.9

1.9

1.9

4.7

6.5

11.2

18.7

2E1-S

20

0.4

0.9

1.9

3.4

3.7

9.4

13.1

22.5

37.4

5E1-S

50

0.9

2.3

4.7

7.3

9.4

23.4

32.7

56.1

93.5

1E2-S

100

1.9

4.7

9.4

14.4

18.7

46.8

65.5

112.3

187.1

2E2-S

200

3.7

9.4

18.7

26.4

37.4

93.5

131.0

224.5

374.2

5E2-S

500

9.4

23.4

46.8

63.8

93.5

233.9

327.4

561.3

935.4

1E3-S

1,000

18.7

46.8

93.5

120.4

187.1

467.7

654.8

1,122.5

1,870.8

2E3-S

2,000

37.4

93.5

187.1

231.9

374.2

935.4

1,309.6

2,245.0

3,741.7

5E3-S

5,000

93.5

233.9

467.7

556.6

935.4

2,338.5

3,274.0

5,612.5

9,354.2

1E4-S

10,000

187.1

467.7

935.4

1,113.1

1,870.8

4,677.1

6,547.9

11,225.0

18,708.3

molbloc-S MASS FLOW RATE (slm @ 0 °C) WHEN molbloc-S UPSTREAM PRESSURE IS:[1][2][1] Flow values in table are valid only when critical flow is established.
[2] When volumetrically based mass flow units with reference temperatures other than 0°C are used, flow values
will generally be higher; the flow values for a given molbloc and upstream pressure are approximately 7%
higher when expressed in slm at 20°C. Flow values at a given pressure may vary by up to ± 2% due toflowpath machining tolerances.
[3] Minimum upstream pressure to achieve critical flow with atmospheric pressure (approximately 100 kPa)downstream of molbloc-S (no vacuum).

© 2010 Fluke Calibration

Page 22

1. INTRODUCTION

1.2.5.2.5

molbloc-S Dimensions
molbloc-S SIZE [mm(in.)]

1E2-S
AND LOWER

2E2-S THRU
1E3-S

2E3-S

5E3-S

1E4-S

A

48.0 (1.89) SQ

48.0 (1.89) SQ

48.0 (1.89) SQ

80.0 (3.15) SQ

B

24.0 (0.94)

24.0 (0.94)

24.0 (0.94)

40.0 (1.57)

40.0 (1.57)

C

48.0 (1.89) SQ

48.0 (1.89) SQ

48.0 (1.89) SQ

80.0 (3.15) SQ

80.0 (3.15) SQ

D80.0 (3.15)

80.0 (3.15)

80.0 (3.15)

176.0 (6.93)

176.0 (6.93)

80.0 (3.15) SQ

E

28.0 (1.10)

28.0 (1.10)

28.0 (1.10)

44.0 (1.73)

44.0 (1.73)

F

167.5 (6.59)

171.0 (6.73)

175.0 (6.89) [1]299.7 (11.80) [1]331.0 (13.03) [1]G

KF16 FLANGEKF16 FLANGEKF16 FLANGE

KF40 FLANGE

KF40 FLANGE

H

100.0 (3.94)

84.0 (3.31)

84.0 (3.31)

154.0 (6.06)

154.0 (6.06)
236.0 (9.29)

I

128.0 (5.04)

128.0 (5.35)

128.0 (5.35)

236.0 (9.29)

J

73.0 (2.87)

73.0 (2.87)

73.0 (2.87)

106.0 (4.17)

106.0 (4.17)

K

167.5 (6.59)

171.0 (6.73)

171.0 (6.73)

290.0 (11.42)

290.0 (11.42)

L¼” VCR Male[2]½” VCR M[2]½” VCR M[2]KF25 FLANGE[2]KF25 FLANGE[2][1] On some molbloc-S elements, the venturi
nozzle extends beyond the molbloc
downstream flange, making the overall
length dimension, F, longer than the fitting
to fitting length dimension, K. The nozzle
overhang may interfere with somemolbloc-S downstream connections or theconnection of a blank off cap for leaktesting, so a 40 mm diameter ISO-KF
nipple is supplied with 5E3-S and 1E4-S
molblocs.
[2] Default connector type is listed. Additional
upstream connector options may beavailable. Contact your FLUKE Sales
Representative for details.

Page 23© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

1.2.6

Front and Rear Panels
1.2.6.1

Front Panel

The front panel assembly provides a 2 x 20 vacuum fluorescent display, amembrane keypad for local user interface and other LED indicators.

 2x20 Display
 Multi-Function Keypad Channel Indicator Remote Operation Indicator

Figure 2. molbox1+ Front Panel

1.2.6.2

Rear Panel

The rear panel assembly provides pressure and electrical connections for two molbloc
mass flow elements, communications interfaces and the power connection module.

 Connection for External DMM (Option)
 External Drivers Connection (Option)
 MFC Switchbox Connection
 RS485 Connection (not used) Host Communications (IEEE-488)
 MFC Analog Control Connection
 Host Communications (RS232)

 Remote Communication for External Device (RS232)
 On/Off Switch
 Fuse molbloc Electrical Connection (Channel B) molbloc Pressure Connections (Channel B) molbloc Pressure Connections (Channel A) molbloc Electrical Connection (Channel A)

Figure 3. Rear Panel© 2010 Fluke Calibration

Page 24

2.

Installation

2.1

Unpacking and Inspection
2.1.1

Removing From Packaging

molbox1+ is delivered, along with its standard accessories, in a corrugated container withfoam end caps to hold it in place.
Remove the molbox1+ and its accessories from the shipping container and remove eachelement from its protective plastic bag.

2.1.2

Inspecting Contents

Check that all items are present and have NO visible damage.
A molbox1+ includes:
Table 25: molbox1+ Parts List
DESCRIPTIONPART #

molbox1+ mass flow terminal

3499975

molbox1+S mass flow terminal

3499975

Report of Calibration

3152121ACCESSORIES INCLUDING:
1

Operation and Maintenance Manual

1Power Cord (7.5 ft.)

35409624molbox to molbloc pressure connecting tubes

2

molbox to molbloc electrical/data connection cables

2

Straight through quick connector stems

1

MFC Cable and Connections Kit (if MFC Option
included)1

External 12 V Drivers Connector

3069839

1

General Accessories Disk (white)(Important: Includes system support software anddocumentation.)

31390433133781or 3153005-CE
3069560
3068683
or 3072220-CE
3068652*
3114778
or 3114784-CE* Equivalent to Swagelok P/N SS-QM2-S-200

2.2

Site Requirements

Install the molbox1+on any stable surface at a convenient height. The front feet are extendible so that theunit can be inclined for easier viewing.

Page 25© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

The molbox1+ can also be mounted in a standard 19 in. rack mount using the optional rack mountkit (P/N 3069903). For additional information, contact your Fluke Calibration Representative.
When installing the molbox1+, consideration should be given to where the molbloc flow measuring
element and associated hardware will be located. molbox1+ may be placed on a shelf or cart at adifferent height than the molbloc, but the distance between the molbloc and molbox is limited by thelength of the cable and pneumatic lines connecting them. If you will locate the molbox at a different
height than the molbloc, the small errors that would be associated with the difference in pressure can beremoved using the molbox1+ head correction (see Section 3.6.8).
If the molbloc/molbox system is being used to calibrate other devices (DUTs), the molbloc may need to beconnected upstream or downstream of the DUT to operate within the pressure limits of the molbloc’s
calibration type (see Sections 1.2.5.1.3, 1.2.5.2.3) and to accommodate the pressure requirements of the DUT.
See the molbloc’s Calibration Report to determine the calibration type of the molbloc you are using.
If the molbloc is connected upstream of the DUT, it is important to supply the molbloc with a stable
regulated gas source. The volume present between the molbloc and the device to be calibrated should
be minimized, particularly for low flows.
In some cases, molbloc-S is used with a vacuum source downstream to reduce the pressure at which
critical flow is reached. Consider the placement of the vacuum pump and connections. Generally, a large
vacuum pump is needed that should be isolated from the work area due to noise and oil vapor
considerations. If the vacuum pump and/or vacuum kit was purchased from Fluke Calibration, see theinstruction sheets and/or manuals that are included with the hardware.
Optional molstics are offered for mounting molblocs. They provide a convenient means of addressing
supply regulation, filtering and interconnection issues with high quality, configured hardware. For additional
information, contact your Fluke Calibration Representative.

 Caution
If a DUT is located upstream of the molbloc and is contaminated, contaminates
may flow from the DUT to the molbloc and alter the molbloc calibration. If the DUT
must be connected upstream of the molbloc, be sure it is clean before flowing andconsider installing a filter between the DUT and the molbloc.

2.3

Initial Setup
2.3.1

Preparing for Operation

To prepare molbox1+ for check out and operation:
 Remove the plastic caps from the molbox1+ rear panel pressure connections.
 Remove the protective plastic sheet from the front panel display.
 Familiarize yourself briefly with the front and rear panels (see Section 1.2.6).
 Follow the steps described in Sections 2.3.2 to 2.3.7.

2.3.2

Power Connection

Connect the power cable supplied to molbox1+ and to a power source. Power requirements
are 85 to 264 VAC, 50 to 60 Hz, 22 VA max. consumption.

© 2010 Fluke Calibration

Page 26

2. INSTALLATION

2.3.3

molbox1+ to molbloc Connections

There are two molbloc connection channels on molbox1+. Each has two pressureconnections (upstream and downstream) and one electrical/data connection. Select achannel to use or connect a separate molbloc to each channel.
For the pressure connections, use the molbox1+ to molbloc pressure tubes (P/N 3069560)
supplied with the molbox1+. Following the color coding on the pressure lines, connect the
upstream (HI) molbox1+ rear panel quick connector to the upstream port of the molbloc andthe downstream (LO) quick connector to the downstream port. To connect the quickconnectors, first pull back the knurled sleeve on the quick connector body, then insert thequick connector stem and push firmly on the quick connectors until they click into place toassure that the connection is properly completed.
For the electrical/data connection, use the molbox to molbloc electrical/data connection cable(P/N 3068683). Connect the cable to the molbloc and then to molbox1+ rear panel connector
labeled molbloc.

 Caution
Avoid making or breaking molbloc electrical connections to the molbox1+
while the molbox power is ON. Damage to the molbloc EEPROM may result.

2.3.4

Gas Supply and Flowpath Connections

Connect a gas supply to the molbloc. Gas supply requirements are:•

The gas supply must be clean and dry (especially free from oil and particulates) to avoid
contaminating the molbloc.

•

For correct measurements, the gas must be of the same species as that selected by themolbox1+ GAS function (see Section 3.4.2). Gas purity affects the measurement
uncertainty of flow measurements as molbox1+ uses the thermodynamic properties ofthe flowing gas in its flow calculations. Generally, gases with purity of 99.9 % or betterare used for molbloc measurements. Except when using ambient air with molbloc-S, thetest gas should be free of any humidity (dewpoint less than – 40 °C).

•

If the molbloc is connected upstream of the DUT, the supply pressure must be regulated
and stable within the limits of the molbloc-L pressure dependent calibration type (seeSection 1.2.5.1.2.1) or molbloc-S calibration type (see section 1.2.5.2.2). If the molbloc isconnected downstream of the DUT, use regulators and valves to make sure that thepressure that is delivered to the molbloc will be within the limits of the molbloc calibration type.

•

Care should also be taken to make sure that the pressure and flow supplied to themolbloc are always low enough to avoid over pressuring the molbox1+ RPTs(seeSections 1.2.2, 3.1.4). If a DUT upstream of the molbloc is operated at high pressure, apressure reducing regulator should be connected between the DUT and the molbloc toensure that even momentary high pressure spikes do not reach the molbox RPTs.

 Caution•

The gas supplied to the molbloc should be clean and dry. Contaminationof the molbloc flow passage with liquids, particulates or any other matter
will alter the molbloc calibration and can lead to out of tolerance flow
measurements.

•

NEVER connect a pressure source to the molbloc that is greater than the
overpressure limit of your molbox1+. molbox1+ A350K overpressure limit
is 300kPa absolute/200 kPa gauge (44 psig/29 psig). molbox1+ A700K
overpressure limit is 650 kPa absolute/550 kPa gauge (95 psia/80 psig).
Overpressure can damage the molbox1+ internal RPTs (see Section 1.2.2,
3.1.4).

Page 27© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

If you are using a DHI molstic: Install the molbloc into the molstic and connect a gas
supply following the molstic instruction sheet or manual. The flow through the molbloc must
be in the direction of the arrow engraved on the molbloc.
If you are NOT using a DHI molstic: Connect a gas supply to the molbloc according to themolbloc instruction sheet and the pressure limits of the molbloc calibration type. A valve
should be installed between the pressure supply and the molbloc to allow flow to the molbloc
to be interrupted. The flow through the molbloc must be in the direction of the arrowengraved on the molbloc.
Adaptor kits are available from Fluke Calibration to make connections from the molbloc or
molstic fittings to other common connector types. Ask you Fluke Calibration Sales
Representative about your specific adaptor requirements.

 Caution
Operating at pressures other than those of the molbloc-L pressure
dependent calibration type (see Section 1.2.5.1.2) or molbloc-S calibration
type may result in out of tolerance flow measurements. Refer to themolbloc Calibration Report to determine its calibration type.

2.3.5

Vacuum Supply (molbloc-S only)

In some cases molbloc-S is operated with a vacuum downstream of the molbloc to reducethe back pressure so that critical flow can be reached at a lower upstream pressure (seeSection 3.1.5).
There is no lower limit to the pressure that may safely be applied to molbox1+ RPTs.
If you are using DHI supplied downstream vacuum connect kit and vacuum pump:
Install the kit and pump following the supplied instruction sheet or manual. Carefully follow
the pump manufacturer’s recommendations for pump operation.
If you are NOT using DHI supplied downstream vacuum connect kit and vacuum pump:
Carefully evaluate vacuum pump specifications to be sure that the vacuum source available
has the pumping speed necessary to safely handle the planned flows and to maintain low
enough pressure at planned flow rates.
Be sure to provide facilities to avoid flowing into the pump when the pump is not ON as thiswill cause pressure to build up on the pump and may damage it. Normally, a shut-off valve
should be included between the pump and the molbloc-S.
It is preferable to install a check valve with very low cracking pressure between the molbloc
and the vacuum shut-off valve.
Adaptor kits are available from Fluke Calibration to make connections from the molbloc or
molstic fittings to other common connector types. Ask you Fluke Calibration Sales
Representative about your specific adaptor requirements.

 Caution
Operating at pressures other than those of the molbloc-S calibration typemay result in out of tolerance flow measurements (see Section 1.2.5.2.2).
Refer to the molbloc Calibration Report to determine its calibration type.

2.3.6

Communications Connections

If molbox1+ is being interfaced to a computer, connect an RS232 cable to molbox1+ COM1or an IEEE-488 cable (cables not supplied) to the molbox1+ IEEE-488 interface. Configure
the interface (see Section 3.6.6).

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2. INSTALLATION

2.3.7

MFC Control Option Connection

If the molbox1+ is equipped with the MFC control option, a cable and connection kit will havebeen supplied with the molbox1+ accessories. Configure the cable correctly using the pinout
information provided in Section 7.3 and information from the MFC manufacturer.

2.4

Power UP and Verification
2.4.1

Power UP

Actuate the power switch on the molbox1+ rear panel. Observe the front panel display as
molbox1+ initializes, error checks, calibrates its internal ohmic measurement system andgoes to the main run screen (see Section 3.2). The top left side of the main run screen
should display a flow value near zero or <BPR HI>. If <NO BLOC> is displayed, molbox1+
has not been able to identify a molbloc connection and load molbloc information. Verify thata valid molbloc is properly connected (see Section 2.3.3) and press [SETUP], <1molbloc> toload the molbloc (see Section 3.5.1). If molbox1+ is still unable to identify a molbloc, themolbloc may require reloading of EEPROM information or molbox1+ may require repair.
If the molbox1+ fails to reach the main run screen: Service may be required. Record thesequence of operations and displays observed and contact a Fluke Calibration Authorized
Service Provider (see Section 7.4).

2.4.2

Check Proper Pressure Measurement Operation

Check that the molbox pressure measurements are operating properly. Proceed as follows: Connect the molbloc to the molbox1+ (see Section 2.3.3).
 Shut off the gas supply to the molbloc and open both molbloc ends to atmospheric(ambient) pressure.
 Press [P&T] and observe the display of the pressure measured by the upstream anddownstream absolute RPTs (see Section 3.4.5).
Observe the upstream anddownstream pressures. These should indicate current atmospheric pressure and be inagreement within ± 0.02% of the nominal full scale calibrated range listed in section
1.2.2. If the two readings disagree by more than this, one or both RPTs may be out ofcalibration and service may be required.
 Press [ESCAPE] to return to the main run screen.

Note
The pressure measurements indicated in the [P&T] screen are corrected
for TARE and AUTOZERO values. If the pressure readings disagree morethan the values indicated above refer to the manual sections regardingthese functions before considering calibration or service.

2.4.3

Check Proper Temperature Measurement Operation

Check that the molbox1+ temperature measurement is operating properly. Proceed as follows: Connect a molbloc to the molbox1+ (see Section 2.3.3).
 From the molbox1+ main run screen, press [P&T] twice to arrive at the temperature display
screen. Observe the temperature readings of the two molbloc PRTs (see Section 3.4.5).
If the molbloc has been in a stable temperature environment for 30 to 60 minutes, thetemperature indications should be roughly ambient temperature and the two indications
should agree within ± 0.2 °C. If the two readings disagree by more than ± 0.2 °C, there
may be a problem with the molbloc or the molbox1+ TEMPERATURE MEASUREMENT
function and service may be required.
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2.4.4

Check the MFC Control Function (Optional)

Using the front panel keypad, display select MFC profile #1 for a voltage MFC or #2 for acurrent MFC (see Section 3.4.8). Using [ENTER] to select MFC setpoints and observing the
MFC display screens, check that the MFC control operation is normal. If operation does notappear to be correct, check the MFC cable configuration and connection. Check therecommendations in Section 2.5 and the Troubleshooting Guide in Section 6 prior tocontacting a Fluke Calibration Authorized Service Provider (Section 7.4).

2.4.5

Leak Check

It is recommended that a new molbox1+ be leak checked at start-up to assure that no internalleaks developed during shipping and handling. See Section 3.4.4.3 to run the molbox1+
on-board INTERNAL LEAK CHECKING function.

2.4.6

Check/Set Security Levelmolbox1+ has a security system based on user levels. By default, the security system is set
to “low”, which includes certain access restrictions, and there is no password required tochange the security level. See Section 3.6.2 for information on the security level system. As
part of the molbox1+ startup, set your desired security level and a password.

 Caution
molbox1+ is delivered with the security level set to “low” to avoid
inadvertent altering of critical internal settings but with access to changing
security levels unrestricted. It is recommended that at least the low
security level be maintained at all times and password protection be
implemented if control over setting of security levels is desired.

2.5

Additional Precautions to Take Before Making Flow
Measurements

Before using the molbox1+ to make meaningful flow measurements, consider the following:•

The pressure measuring RPTs must be tared at the operating line pressure (see Section 3.4.4.1).

•

Operating pressure and flow range should be within the limits of the molbloc calibration type andmolbloc size for the flowing gas (see Section 1.2.5).

•

Be sure that the gas pressure connected to the molbloc is not great enough to overpressure themolbox1+ internal RPTs.

•

The gas type selected should be the gas flowing through the molbloc (see Section 3.4.2).

•

For flow measurement uncertainty within molbox1+ specifications, the gas type should be a gas withwhich the molbloc has been calibrated (see molbloc Calibration Report) or press [SETUP], <1molbloc>,[ENTER] to see if the gas is included in the molbloc calibration gas list (see Section 3.5.1).

•

Be sure the flow unit of measure you are using is correct. The default flow units of sccm and slm forany molbox1+ are referenced to 0°C and 101.325kPa per SEMI E12-96. Many different types of flow
units of measure are commonly used and have similar names. Before selecting a unit of measure,familiarize yourself with Section 3.4.3 and its subsections thoroughly.

•

Do not supply a gas or connect a DUT upstream of the molbloc that may contaminate the molbloc.
The filter assembly inside a molbloc-L is designed to work with a clean gas supply with limited
contaminants. This filter assembly should be considered a last line of defense against contamination
and additional filtration should always be considered.

•Troubleshooting: For information on typically encountered start-up and operational issues, see Section 6.

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2. INSTALLATION

2.6

Short Term Storage

The following is recommended for short term storage of molbox1+:•

Vent the molbox1+ pressure ports.

•

Turn off the power.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Notes© 2010 Fluke Calibration

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3.

Operation

3.1

General Operating Principles
3.1.1

molbloc Channel A & Channel B

molbox1+ supports two molbloc input channels. The main purpose of this capability is to switch
conveniently between two molblocs without making and breaking connections, for example,
to switch between two ranges. It also allows two molblocs to be used simultaneously(see Section 3.5.4).
The active molbox1+ channel is indicated by the lit LED under the display. The active
channel can be changed by pressing the [A/B] direct function key (see Section 3.4.7). Whena molbloc channel is activated, molbox1+ operates internal valves to connect the molbloc
pressure ports for that channel to the molbox1+ pressure transducers. The temperature of
the molbloc connected to the active channel is measured and the flow calibration data for the
molbloc most recently activated on that channel is used for calculating flow.

Channel A High Isolation: OpenChannel A Low Isolation: OpenChannel B High Isolation: Closed
Channel B Low Isolation: Closed
Bypass: Closed, molbox1+-S does not use this valve
or connection.

Figure 4. molbox1+ Internal Pneumatic Schematic - CHANNEL A ACTIVE, molbloc-L OPERATION

User-selected settings such as gas, units, K factor, etc. are all common between channels A and
B. When one of these settings is changed while channel A is active, that setting will also be madefor channel B, even if different molbloc types are connected to the two channels. The only settingthat is not common to both molbloc channels is the tare value (See Section 3.4.4).

3.1.2

molbloc-L and molbloc-S Operation

molbox1+ operates somewhat differently depending on whether a molbloc-L or molbloc-S isconnected to the active molbox1+ channel. mobloc-L and molbloc-S operation use different
displays and flow calculations and some menu items are present for only one type of molbloc.
Most molbox1+ settings, such as gas, units, K factor, etc., are common to both molbloc-L andmolbloc-S operation. Changes made to these settings while operating one type of molbloc
will still be in effect when the other type of molbloc is connected. The only setting that exists
for both molbloc types, but is stored independently for each type, is the tare value. See
section 3.4.4.1 for details on the tare function.
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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Several of the molbox1+ screen displays and functions described in this section are different
for molbloc-L and molbloc-S operation. Where the differences are major, the description ofthese functions is divided into two parts.

3.1.3

Flow Ready/Not Ready Indication

The character to the left of the measured flow on the MAIN run screen provides a flow
Ready/Not Ready indication. This indication is intended to provide the user with a clear andobjective indication of when a stable flow has been achieved.
Ready <*> is indicated when the current stability (rate of change) of flow is less than thestability limit. The user can set the stability limit (see Section 3.5.2). The Ready/Not Ready
indication is often used when comparing the molbox1+ and a test device to help determine
when steady state flow conditions are present so that a valid comparison reading can be made.
In addition to the conditions listed in sections 3.1.3.1 and 3.1.3.2 molblocs that have named
calibration support will flash the flow display and indicate a Not Ready condition when themeasured flow exceeds the calibrated flow range by 5% or the measured upstream pressure
exceeds the calibrated pressure range by 10 kPa above the maximum pressure or 10 kPa
below the minimum pressure. The downsream pressure is used when a molbloc-L
downstream calibration is active.

3.1.3.1

molbloc-L Operation

In molbloc-L operation, the Ready/Not Ready indication also helps guard against
using molblocs above their valid range by monitoring the Reynolds number of theflow. If the Reynolds number of the current flow exceeds 1 300, the Ready (<*>)
indicator flashes. The current Reynolds number value can be viewed using[P&T] (see Section 3.4.5). If molblocs are used within the pressure and flow
range limits for the flowing gas and the pressure dependent calibration type(see Section 1.2.5), a Reynolds number of 1 200 will never be exceeded (1 300
is used as the warning limit to allow for individual molbloc differences).
Ready/Not Ready character indications are:<*>Flow Ready (stable).

<*>(Flashing): Reynolds number > 1 300.

<↓>

Flow Not Ready (unstable and decreasing).

<↑>

Flow Not Ready (unstable and increasing).

<P>

Flow Not Ready, flow flashes (pressure exceeds calibratedpressure range by 10kPa)<F>

Flow Not Ready, flow flashes (flow exceeds calibrated max flow by 5%)

3.1.3.2

molbloc-S Operation

In molbloc-S operation, the Ready/Not Ready indication is also used to warn theuser when the BPR (back pressure ratio) is too high to ensure critical flow (seeSection 3.1.5). When the BPR is beyond the choking limit, molbloc-S flow
measurements may not be valid and the Ready indicator becomes <P>. The
Ready/Not Ready indicators based on flow stability are also used in molbloc-S
operation, but the <P> indicator takes priority over other indicators.

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3. OPERATION

Ready/Not Ready character indications are:

3.1.4

<*>

Flow Ready (stable).

<↓>

Flow Not Ready (unstable and decreasing).

<↑>

Flow Not Ready (unstable and increasing).

<P>

Flow Not Ready (BPR high / sub-critical flow)<P>[Alternate] Flow Not Ready, flow flashes (pressure exceeds calibratedpressure range by 10kPa)<F>

Flow Not Ready, flow flashes (flow exceeds calibrated max flow by 5%)

Reference Pressure Transducer (RPT) Overpressuremolbox1+ has two absolute RPTs, one measures molbloc upstream pressure,the other measures molbloc downstream pressure and may provide a second
measurement of molbloc upstream pressure in molbloc-S operation. In normal
operation, they are not used at pressures greater than the following maximum
working pressures:molbox1+ A350K: 300 kPa absolute (44 psia)
molbox1+ A700K: 600 kPa absolute (87 psia)
molbox1+S A1.4M: 1400 kPa absolute (203 psia)
molbox1+S A2M: 2000 kPa absolute (290 psia)
Exposing the molbox1+ RPTs to pressures greater than the maximum operatingpressure may damage them. molbox1+ has a system of warnings and alarms toprotect itself from overpressure (see Section 3.6.3.1).

3.1.5

molbloc-S BPR Limits

To make flow measurements within predictable measurement uncertainty limits with a molbloc-S
flow element, critical (sonic) flow conditions must be present. Critical flow exists when thegas velocity reaches the local speed of sound at the throat of the molbloc-S Venturi nozzle.
molbox1+ uses the back pressure ratio, or BPR (the ratio of the molbloc-S downstream
absolute pressure to the upstream absolute pressure) to determine whether the flow is critical.
For Venturi nozzles in general, the BPR must remain below a certain value for critical flow toexist. Commonly accepted practice for critical flow orifice use suggests that this limiting BPR
value, or “choking ratio”, is approximately 0.5. That is, the absolute pressure downstream of
the nozzle must be less than one half of the absolute pressure upstream of the nozzle.
Empirical study of the Venturi nozzles used in molbloc-S shows that the actual choking ratio,or maximum BPR for critical flow, varies between about 0.4 and 0.9 as a function of the
Reynolds number (Re) over which the molblocs are used. molbox1+ continually calculates
Re during flow measurement and can monitor the BPR to ensure that it does not exceed thechoking ratio at the current Re conditions. molbox1+ uses a conservative BPR limit toindicate to the user when the BPR approaches the choking ratio, to ensure that flow
measurements are only made under “safe” critical flow conditions. molbox1+ includes
features to measure BPR, automatically alert the operator when the BPR is too high andprevent measurements when flow is not critical (see Sections 3.1.3.1, 3.4.4.5, 3.6.9).
Maintaining a sufficiently low BPR must be considered by molbloc-S users when selecting
molbloc-S sizes and hardware setups to use for flow measurements. For example, if amolbloc-S will be used with atmospheric pressure downstream, then the molbloc can only be
used over a range of upstream pressures starting at the maximum pressure for its calibration
type down to a minimum pressure value at which the BPR becomes equal to the BPR limit
calculated by molbox1+. Since mass flow through molbloc-S is proportional to the upstream
absolute pressure, the flow range for the molbloc in this application is defined by the BPR

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

limit also. To maximize the range of a molbloc-S element, a vacuum pump can be connected
downstream to reduce the downstream pressure while flowing. When the downstreampressure is kept sufficiently low, the upstream pressure, and thus the mass flow rate, can be
adjusted all the way down to the minimum value for the molbloc’s pressure dependentcalibration type without being limited by the BPR value.
Depending on the placement of the molbloc-S in relation to the DUT and other hardware, andthe availability and capacity of a vacuum pump that may be used, the molbloc-S downstreampressure will vary in different applications. Calculating Re for different molbloc-S sizes andflow rates, and estimating the choking ratio (maximum BPR limit) as a function of Re issomewhat complex, so Table 17 is offered as an example of the minimum flow that can beachieved with each molbloc-S size in nitrogen, without exceeding molbox1+ BPR limits, whenthe molbloc-S downstream pressure is known: In actual operation, molbox1+ calculates theRe and BPR ratio and can automatically provide an indication of whether the BPR is adequate formeasurements to be made. For an estimate of the minimum critical flow at various downstreampressures in gases other than N2, contact your Fluke Calibration Representative.
Table 26: Minimum molbloc-S Critical Flow (slm) in Nitrogen at Various molbloc-S Downstream Pressures
N2 MINIMUM molbloc-S CRITICAL FLOW [SLM @ 0°C] WITH MOLBLOC DOWNSTREAM PRESSURE OF:[1]molbloc-S
DESIGNATOR

≤5
kPa
(0.7
psia)

10
kPa
(1.5
psia)

25
kPa
(3.5
psia)

50
kPa
(7
psia)

100
kPa
(15
psia)

110
kPa
(16
psia)

125
kPa
(18
psia)

150
kPa
(22
psia)

200
kPa
(30
psia)

250
kPa
(36
psia)

300
kPa
(44
psia)

1E1-S

0.2[2]

0.4

0.9

1.1

1.8

2.0

2.2

2.4

2.8

3.5

4.2

2E1-S

[2]

0.7

1.6

1.8

3.2

3.5

3.7

4.2

5.6

7.0

7.6

[2]

1.7

3.4

4.7

7.7

8.4

9.4

11

14

17

20

[2]

3.4

5.9

8.4

15

16

18

21

27

33

38

[2]

5.9

9.8

16

28

31

34

40

51

63

74

[2]

12

20

37

67

72

80

95

122

149

179

[2]

[2]

39

69

129

139

154

184

239

294

349

[2]

73

131

248

268

298

358

468

578

687

[2]

173

317

596

646

746

871

1 145

1 420

1 694

[2]

347

615

1 173

1 273

1 442

1 741

2 240

2 789

3 338

5E1-S
1E2-S
2E2-S
5E2-S
1E3-S
2E3-S
5E3-S
1E4-S

0.4
1

2
4

10
20

[2]

40

[2]

100

[2]

200

20
40
100
200

[1] When volumetrically based mass flow units with reference temperatures other than 0 °C are used, flow values will
generally be higher; for example, the flow values for a given molbloc and upstream pressure are approximately 7 % higher
when expressed in slm @ 20 °C. Flow values at a given pressure may vary by up to 2 % due to flowpath machining
tolerances.
[2] Limited by 20 kPa minimum calibration pressure rather than back pressure ratio

3.2

Main Run Screen

The molbox1+ MAIN run screen is its home display that is reached on power up and from which otherfunctions and menus are accessed. It is the top level of all menu structures.
The MAIN run screen is displayed in normal operation. It indicates the current measured flow as well as avariety of additional information, if desired.
The MAIN run screen display applies to the molbloc on the active molbloc channel indicated by the red
LED below the molbox1+ display (A or B). The appearance of the MAIN run screen differs depending onwhether the active molbloc is a molbloc-L or a molbloc-S.

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3. OPERATION

3.2.1

molbloc-L Operation

Some items in the molbloc-L MAIN run screen may change or flash at times, to indicate thatcertain limits are exceeded, as described in the text accompanying the following screen display:1.

<*> Ready/Not Ready indication; <*> when Ready (flashes if
Reynolds number of the flow exceeds 1 300), <↑>(increasing) or <↓> (decreasing) indicating direction of flowrate evolution when Not Ready (see Section 3.1.3).

2.

<FLOWWWW>: Numerical value and sign of the flow
measured by molbox1+. Result of last flow averaging cycle if in
AVERAGE display (see Section 3.4.6.2). Flashes if Reynolds
number of the flow exceeds 1,300. Flashing also occurs when anamed calibration is active and the flow exceeds the calibrated
range by 5%, or the measured upstream pressure exceeds thecalibrated pressure range by 10 kPa above the maximum
pressure or 10 kPa below the minimum pressure. The
downsream pressure is used when a molbloc-L downstream
calibration is active. The field displays “PMODEL” when thepressure exceeds the molbox internal pressure model for theactive calibration gas.

*FLOWWWW unitk GGGGD DISPLAY MODE DATA MFC1R

3.

<UNIT>

Current flow unit of measure (see Section 3.4.3). Flashes if BPR is higher than the choking limit.

4.

<K>: Indication whether a gas conversion factor or ADJ flow adjustment is applied to the displayed flow
measurement. Possible indications include:<K>: Indicates that a gas correction factor (K factor) is currently being applied to the measured flow (seeSection 3.4.1). <K> if a factor is being applied, blank if no factor is being applied.
<A>: Indicates that a flow adjustment adder and/or multiplier) is currently being applied to the measured flowusing the ADJ function (see Section 3.5.3). <A> if ADJ is being applied, blank if no ADJ is
being applied. Alternating When both ADJ and a K factor are applied, the indication alternates between<k> and <A> at each screen update.

5.

<GGGG>: Indicates the current molbox gas selection (see Section 3.4.2). This should be the gas that is
flowing through the molbloc. The field will alternate with the named calibration name when a named
calibration is active and more than one calibration is available for the selected gas.

6.

<D>: Indication of what is being displayed on the bottom line of the display as set by the DISPLAY function(see Section 3.4.6). Possible indications include:<R>:

Current DISPLAY mode is RATE (see Section 3.4.6.1); or if <n avg> is in the bottom right hand cornerof the display, current DISPLAY mode is “average” and this is the instantaneous reading AVERAGE
screen (see Section 3.4.6.2).

<σ>Current DISPLAY mode is AVERAGE (see Section 3.4.6.2).

<H>

Current DISPLAY mode is HI/LO (see Section 3.4.6.3).

<∑>

Current DISPLAY mode is TOTAL (see Section 3.4.6.4).

<=>

Current DISPLAY mode is UNIT (see Section 3.4.6.5).

<D>

Current DISPLAY mode is DEVIATION (see Section 3.4.6.6).

<F>

Current DISPLAY mode is FREEZE (see Section 3.4.6.7).

Blank, No character

Current DISPLAY mode is CLEAN (see Section 3.4.6.8).

7.

<DISPLAY MODE DATA>:
Section 3.4.6).

Information displayed depends on current display mode (see8.

<MFC1R>: If the molbox1+ has the MFC control option, MFC profile and MFC switchbox channel number are
displayed when MFC function is on. Followed by R if MFC is in regulation mode. This display is overridden
by <DISPLAY MODE DATA> if the space is needed to display <DISPLAY MODE DATA> (Average, Hi/Lo,
Total, Unit, Deviation).

Note•

The MAIN run screen may be slightly different when MFC control is in use
or an A_B function is in use (see Sections 3.4.8, 3.4.7).

•

When a number is too large to show in the allocated display space,molbox1+ displays <********>.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL•

molbox1+ has a SCREEN SAVER function that causes the display to dim if
NO key is pressed for 10 minutes. Pressing a key restores full power tothe display. The screen saver activation time can be changed or screen
saving can be completely suppressed (see Section 3.6.5.1).

3.2.2

molbloc-S Operation

As with molbloc-L there are limits on some of the conditions that may exist if the user expects
to make accurate flow measurements with molbloc-S. The key condition that can be monitored isthe back pressure ratio, or BPR, which determines whether critical flow through the molbloc isachieved (see Section 3.1.5).
When the BPR is in a “safe” region for critical flow measurements, the appearance of theMAIN run screen is identical to the MAIN run screen in molbloc-L operation (see Section
3.1.3.1). When the molbox1+ BPR limit is exceeded, there are two possible MAIN run screen
indicators. A flashing flow value and unit indicate that the BPR limit has been exceeded. In
this condition, the flow may not be critical and flow measurements should not be relied on tomeet specifications. When the BPR limit is exceeded by a large margin, the flow is almost
certainly not critical and the calculated value may be non-sensical, so the flow value is notshown and is replaced by <BPR HI>. In this state, the BPR value replaces the display fieldon the second line of the molbox1+ terminal.

Note
When molbloc-S is in the BPR OFF mode (see Section 3.6.9), BPR is notmonitored and invalid flow values may be displayed in the molbloc-S MAIN
run screen with no indication that a the BPR value is high.
1.

<*> Ready/Not Ready indication; <*> when Ready <↑>(increasing) or <↓> (decreasing) indicating direction of flowrate evolution when Not Ready; <P> when BPR is higher
than choking limit. (see Section 3.1.5).

2.

<FLOWWWW>: Numerical value and sign of the flow
measured by molbox1+. Result of last flow averaging cycle
if in AVERAGE display (see Section 3.4.6.2). Flashes if
BPR is higher than the choking limit. If BPR exceeds thechoking limit by a large margin, <BPR HI> replaces the flow
value. The flow will flash when a named calibration is active
and the flow exceeds the calibrated range by 5% or themeasured upstream pressure exceeds the calibratedpressure range by 10 kPa above the maximum pressure or
10 kPa below the minimum pressure. The field displays“PMODEL” when the pressure exceeds the molbox internalpressure model for the active calibration gas.

*FLOWWWW unitk GGGGD DISPLAY MODE DATA MFC1R

3.

<UNIT>

Current flow unit of measure (see Section 3.4.3). Flashes if BPR is higher than the choking limit.

4.

<K>: Indication whether a gas conversion factor or ADJ flow adjustment is applied to the displayed flow
measurement. Possible indications include:<K>: Indicates that a gas correction factor (K factor) is currently being applied to the measured flow (seeSection 3.4.1). <K> if a factor is being applied, blank if no factor is being applied.
<A>: Indicates that a flow adjustment adder and/or multiplier) is currently being applied to the measured flowusing the ADJ function (see Section 3.5.3). <A> if ADJ is being applied, blank if no ADJ is
being applied. Alternating When both ADJ and a K factor are applied, the indication alternates between<k> and <A> at each screen update.

5.

<GGGG>: Indicates the current molbox gas selection (see Section 3.4.2). This should be the gas that is
flowing through the molbloc. <AirW> indicates that air is selected and a humidity correction is being applied(see Section 3.4.2.2). The field will alternate with the named calibration name when a named calibration is
active and more than one calibration is available for the selected gas.

6.

<D>: Same as molbloc-L (see Section 3.1.3.1).

7.

<DISPLAY MODE DATA>: Information displayed depends on current display mode (see Section 3.4.6).

8.

<MFC1R>: Same as molbloc-L (see Section 3.1.3.1).

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3. OPERATION

Note

3.3

•

The MAIN run screen may be slightly different when MFC control is in use
or an A_B function is in use (see Sections 3.4.8, 3.4.7).

•

When a number is too large to show in the allocated display space,molbox1+ displays <********>.

•

molbox1+ has a SCREEN SAVER function that causes the display to dim if
NO key is pressed for 10 minutes. Pressing a key restores full power tothe display. The screen saver activation time can be changed or screen
saving can be completely suppressed (see Section 3.6.5.1).

Manual Operation
molbox1+ is designed to offer the optimum balance between simple, intuitive operation andthe availability of a wide variety of functions with a high level of operator discretion. The local
operator interface is through the front panel’s 2 x 20 character alpha-numeric display and a
4 x 4 multi-function keypad. Remote operation by RS232 or IEEE-488 interface is alsoavailable (see Section 4).

3.3.1

Keypad Layout and Protocol

molbox1+ has a 4 x 4 keypad for local operator access to direct functions, function menus
and for data entry.



The Editing and Execution keys are for
execution, suspending execution, backing up inmenus and editing entries.



The Menu/Data keys provide access to function
menus from the MAIN run screen. The menu
name is on the bottom half of the key. The SETUP
menu is for more frequently used functions. The
SPECIAL menu is for less frequently used andinternal functions. These keys enter numericalvalues when editing.



The Function/Data keys allow very commonlyused functions to be accessed directly from theMAIN run screen by a single keystroke. The name of
the function is on the bottom half of the key (seeSection 3.3.2). These keys enter numerical values
when editing.

Figure 5. Keypad Layout

Pressing the [ENTER] key generally causes execution or forward movement in the menu tree.
Pressing the [ESCAPE] key generally allows movement back in the menu tree and/or causes
execution to cease or suspend without changes being implemented. Pressing [ESCAPE]
repeatedly eventually returns to the MAIN run screen. From the MAIN run screen, pressing[ESCAPE] allows momentary viewing of the molbox1+ identification screen.
Pressing the [+/-] key changes a numerical sign when editing.
multiple screens when available.

It also toggles throughPressing the [←] and [→] keys allows reverse and forward cursor movement when editing
data entry. These keys are also used to scroll through choices.
Menu selections can be made by pressing the number of the selection directly or by pressing [←]and [→] to place the cursor on the number of the desired selection and pressing [ENTER].
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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Note
Some screens go beyond the two lines provided by the display. This isindicated by a flashing arrow in the second line of the display. Press [←]and [→] to move the cursor to access the lines that are NOT visible ordirectly enter the number of the hidden menu choice if you know it.

3.3.2

Direct Function Keys Summary

Local operation of molbox1+ is through the front panel 4 x 4 pressure sensitive keypad. To
minimize the use of multi-layered menu structures, the keypad numerical keys also provide directaccess to the most commonly used functions. The function accessed is labeled on the bottom
half of the each key. Direct function keys are active whenever molbox1+ is in its MAIN run
screen. Table 27 summarizes the operation of the direct function keys. See corresponding
manual sections for full detail on each direct function.

Note
It may be useful to keep a copy of Error! Reference source not found.,
Summary of molbox1+ Direct Function Key Operations, near themolbox1+, especially when first becoming acquainted with its operation.
Table 27: Summary of molbox1+ Direct Function Key Operations
Direct Function Keys Are Active From The Main Run Screen
See Corresponding Manual Sections For Full DetailMenu of commonly used setup features including MFC profiles, stability setting andsecondary unit changes.
Menu of less frequently used internal functions and settings including preferences, resets,remote interfaces, BPR (back pressure ratio) when using molbloc-S.

Select active molbloc channel.

Turn on the MFC control option, select MFC profile to use and MFC switchbox channel.

Set the resolution with which the measured flow and other values are displayed.

Run the TARE, LEAK CHECK, PURGE and AutoZ functions. The option to TARE is notavailable in a molbox1+S.
Display the current pressure measurements (first press).
Display the current molbloc temperature measurements (second press).
Define the DISPLAY function for the second line of the molbox1+ display. Choices includerate, average, hi/lo, totalize, 2nd unit, deviation, freeze, clean.

Set/change a DUT gas correction factor (K factor).

Set flow measurement gas. This is also the key used to access and select named gas
calibrations on a molbloc.

Set flow measurement unit. Choice of units can be customized.

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3. OPERATION

3.4

Direct Function Keys
3.4.1

[K]

 PURPOSE
To cause the flow value calculated by molbox1+ to be multiplied by a factor, K. Generally used
to apply a test device’s gas correction factor used when a test device is calibrated with a gas
other than its normal gas.
 PRINCIPLE
Frequently, when testing or calibrating a flow measuring device, it is not possible to flow thegas with which that device will normally be operated (the process gas). This may be
because the process gas is toxic or corrosive or simply because it is not available. When theprocess gas cannot be used for calibration, it is common to use a different gas for testing or
calibrating (the calibration gas). In this case, a factor representing the relationship between
the calibration gas and the process gas for the test device may be applied so that thecalibration gas simulates the process gas. The calibration gas that simulates theprocess gas is often called a surrogate gas for the process gas.
The relationship between a test device’s process gas and calibration gas is frequently
called a K factor or gas conversion factor. The factor’s value depends on specific propertiesof the test device and determining the value is the responsibility of the device manufacturer.
For example, Silane (SiH4) is a frequently used gas in semiconductor processing. SiH4 ishighly toxic and requires extensive handling precautions so it is not practical for use incalibration and testing. A major manufacturer of Mass Flow Controllers (MFCs) recommends
that MFCs that are to be used with Silane be tested with Sulfur Hexafluoride (SF6), a nontoxic, non-flammable gas, using a conversion factor of 0.970. In other words:
SF6 flow x 0.970 = equivalent SiH4 flow for the MFC
The K function in molbox1+ allows a gas conversion factor to be entered by which flow values
measured by molbox1+ will be multiplied. In this example, 0.970 would be entered as K sothat the values indicated by molbox1+ when SF6 is flowing through the molbloc simulate theflow of SiH4 for that manufacturer's MFC.
When the K function is active, molbox1+ performs all of its flow calculations normally but
multiplies the current flow value by the value of the K factor prior to displaying it.
The gas selected on molbox1+ which is displayed in the upper right corner of the molbox1+
display should always be the gas that is actually flowing through the molbloc.

Note
K factors or gas conversion factors are based on the properties of thedevice being tested. Their availability and validity are the responsibility ofthat device's manufacturer. molbox/molbloc does not use factors orconversion coefficients between gases. Flow is calculated from molbloc
characteristics and specific gas properties for each gas supported bymolbox1+. The gas selected on molbox1+ (see Section 3.4.2) which isdisplayed in the upper right corner of the molbox1+ display should always
be the gas that is actually flowing through the molbloc.
 OPERATIONTo enable a gas conversion factor press [K] from any
run screen. The display is:

K Factor?
1on 2off

If <2off> is selected, no conversion factor will
be applied. If <1on> is selected, the next screen is:

K Factor:
1.00000

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

The value of the gas conversion factor can be edited as desired. Pressing [ENTER] returns
to the MAIN run screen with the entered K factor active. The letter <K> is always
appended to the flow unit indication in the run screens when the K function is ON(e.g., sccmK). A K factor value of 1 is handled as if the K function were OFF.

 Caution
When the K function is ON, as indicated by a <K> following the current
flow unit in the first line of the MAIN run screen, the current molbox1+ flow
indication is:(flow as calculated by molbox1+ for the selected gas) x (the current K
factor)Thus, the flow indicated is actually in error (biased) by the reciprocal of the
K factor.

3.4.2

[GAS]

 PURPOSE
To specify the gas that is currently flowing through the molbloc so that molbox1+ uses thecorrect gas properties in its flow calculations.
 PRINCIPLE
molbox1+ calculates the flow through a molbloc from:•molbloc geometric characteristics•

gas pressures•

gas temperature•

specific characteristics of the flowing gas

The gas characteristics include:•gas density under standard conditions•

change in gas density with pressure and temperature•

gas viscosity under standard conditions (when needed)•changes in gas viscosity with pressure and temperature

Proprietary algorithms are used to calculate gas density and viscosity (when needed) under
the actual flowing pressure and temperature conditions from density and viscosity understandard conditions.
The characteristics of molbox1+ supported gases and corresponding algorithms are stored inmolbox1+ memory. To correctly calculate the flow of a gas, the correct information for thatgas must be used. The molbox1+ GAS function allows the user to specify the flowing gas sothat molbox1+ will use the correct gas information in calculating the flow through the molbloc.
Selection of a gas using the GAS function also selects the molbloc (geometric) calibration data to
be used for flow calculation. If a calibration has been stored in the molbloc for the selected gas,
the molbloc calibration data for that gas are used. If a gas is selected that the molbloc is notcalibrated for, the molbox1+ will use the coefficients of the default gas, normally N2 for molbloc-L
and Air for molbloc-S. In the case that there are multiple N2 or Air calibrations on the molbloc, thecoefficients for the calibration indicated as DEFAULT on the calibration report are used. When acalibration has not been performed on the molbloc in the gas selected using the GAS function,
flow measurements have NO associated uncertainty or tolerance.
The operation of the GAS function, is different for molbloc-L and molbloc-S due to the support ofhumid air measurements with molbloc-S. They are described separately below.

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3. OPERATION

3.4.2.1

molbloc-L Operation

The molbox1+ gases available for use with molbloc-L at the time of this manual
printing are listed in Table 19.
Table 28. Available molbloc-L Gases<1inert><2flammable><3toxic><1CO> Carbon Monoxide<4other><1N2> Nitrogen<1H2>

Hydrogen<1Air>

Air<2He> Helium<2O2>

Oxygen<2C2F6>

Hexafluoroethane<3Ar> Argon<3CH4>

Methane<3N2O>

Nitrous Oxide<4C2H4> Ethylene<4CF4>

Carbon Tetrafluoride<5C3H8> Propane<5SF6>

Sulfur Hexafluoride<6C2H6> Ethane<6CHF3> Fluoroform<7Butn> Butane<7C02>

Carbon Dioxide

<8Xe>

Xenon

<9C4F8>Octofluorocyclobutane

Note•<Butn> is used to identify Butane in molbox1+ because thechemical symbol for Butane (C4H10) has more than the 4characters used by molbox1+ to abbreviate gas
identifications.

•

Mixtures of known gases in known concentrations can bemeasured by calculation and use of the ADJ function (seeSection 3.5.3).

 OPERATION (molbloc-L Operation)
To specify the gas flowing through molbloc-L,press [GAS]. The display is:
The gases available are grouped in categories
to facilitate finding a specific gas and as areminder to the user when selecting a gas that
may require special precautions in use. Thereis a list of gases under each category. For
example, the <1inert> selection displays:
A secondary menu displays when a specificallycalibrated gas is selected. The menu includes:
the name of the gas, calibration name, thecalibrated flow range, the calibration type
(PREM for premium or STD for standard) andthe supported pressure range. If multiple
calibrations are available for the selected gas
arrow keys “<>” display after the pressure. Use
the left right arrow keys to select the othercalibrations.
If the selected gas is not specifically calibrated
on the molbloc a secondary menu displays
indicating that the default calibration for the
molbloc will be used to derive the flow of theselected gas. Press enter to proceed.

1inert 2flammable
3toxic 4other
1N2

2He

3Ar

He, HI 5.0 slm
STD 50-550 kPa <>No Air cal, N2
used [ENTER]

coef

Select the desired gas. Pressing [ENTER] returns to the last run screen withthe selected gas active. The selected gas is always displayed in the upper righthand corner of the MAIN run screen.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALNote
The gas selected on the molbox1+ should always be the gasthat is flowing through the molbloc. molbloc/molbox does not
use K factors or gas conversion factors between gases. Whencalibrating or testing a device with a surrogate gas, molbox1+
should be set to the surrogate gas. The K factor or gas
conversion factor, if used, defines the relationship between thesurrogate gas and the process gas for the device being tested,
not for molbox1+ (see Section 3.4.1, PRINCIPLE). The K factor
is supplied by the manufacturer of the device being tested.

3.4.2.2

molbloc-S Operation

In addition to dry air, molbox1+ supports measurement of ambient (humid) air
flow with molbloc-S. When Air is selected as the molbloc-S test gas, the user is
prompted to enter a value of the humidity ratio (also known as the absolute
humidity or water ratio) of the ambient air. The humidity ratio, W, is defined as
the ratio of water mass to gas mass in the flowing air. It is different from therelative humidity value, which is usually expressed as a percentage. Typical valuesof W are between zero and 0.06. molbox1+ does not accept an entry for W
greater than 0.1.
Typically, humidity measuring instruments report relative humidity, which isdependent on the ambient pressure and temperature. Users who do not havethe W value available can use Fluke Calibration’s free Unit of Measure
Converter software utility or COMPASS for molbox or COMPASS for Flowcalibration software to calculate W from measured pressure, temperature, andrelative humidity. Visit www.dhinstruments.com, or see your Fluke Calibration
sales representative for a copy of the Unit of Measure Converter software utility.
Air relative humidity, pressure and temperature are converted to the humidity
ratio, W, following Dalton’s Rule and thermodynamic principals using water
saturation properties:

 RH 
Pg ⋅ 

 100 W = .62188 ⋅ RH 
Pamb − Pg ⋅  100 Pg is the water saturation pressure, which can be calculated as:
Pg = C 0Tamb + C1Tamb + C 2Tamb + C 3
3

2

where :
C 0 = 0.0649289
C1 = −53.0528
C 2 = 14509.9
C 3 = −1327760
If dry air will be measured, then the user should enter a W value of zero when
prompted. Zero is the default W value.
When a non-zero W value is entered, molbox applies a correction to its air flow
measurement for the change in air density due to humidity. If a correction for W
is being applied to air flow measurements, a <W> is placed to the right of the<Air> gas indication in the MAIN run screen.

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3. OPERATION

The humid air correction applied to the molbloc measured flow is (from ASMEFEDSM98-5309):

qm(ratio) = a + bW + cW 2 + dW 3
where :
a = 1.0000
b = −0.336872
c = 0.158514
d = 0.131924
Note
If an incorrect value of W is entered (for example, using any
non-zero W value while flowing dry air), an error will be
introduced into the air flow measurement. W, humidity ratio, isdifferent from relative humidity.


OPERATION (molbloc-S Operation)

To specify the gas flowing through molbloc-S,press [GAS]. The display is:
The gases available are grouped in categories
to facilitate finding a specific gas and as areminder to the user when selecting a gas that
may require special precautions in use. Thereis a list of gases under each category. For
example, the <4other> selection displays:
A secondary menu displays when a specificallycalibrated gas is selected. The menu includes:
the name of the gas, calibration name, thecalibrated flow range, the calibration type
(PREM for premium or STD for standard) andthe supported pressure range. If multiple
calibrations are available for the selected gas
arrow keys “<>” display after the pressure.
Use the left right arrow keys to select the othercalibrations.

1inert 2flammable
3toxic 4other

1Air
4CO2

2N2O

3SF6

N2 , HI 5.0 slm
STD 50-550 kPa <>If the selected gas is not specifically calibrated
on the molbloc a secondary menu displays
indicating that the default calibration for the
molbloc will be used to derive the flow of theselected gas. Press enter to proceed.

No N2 cal, Air
coef used [ENTER]

Select the desired gas. If <1Air> is selected,
the display is:

Humidity ratio:
0:1

Leave the value at zero when dry air is being flowed. Enter the appropriate nonzero value (see section immediately above) if humid air is being flowed.
Pressing [ENTER] returns to the last run screen with the selected gas active.
The selected gas is always displayed in the upper right hand corner of the MAIN
run screen.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALNote
The gas selected on the molbox1+ should always be the gasthat is flowing through the molbloc. molbloc/molbox does not
use K factors or gas conversion factors between gases. Whencalibrating or testing a device with a surrogate gas, molbox1+
should be set to the surrogate gas. The K factor or gas
conversion factor, if used, defines the relationship between thesurrogate gas and the process gas for the device being tested,
not for molbox1+ (see Section 3.4.1, PRINCIPLE). The K factor
is supplied by the manufacturer of the device being tested.

3.4.3[UNIT]

 PURPOSE
To specify the flow unit of measure in which molbox1+ displays measured flow values.
 PRINCIPLE
molbox1+ calculates the mass flow of various gases in kilograms/second [kg/s]. molbox1+
also supports conversions to a variety of other flow units of measure. The UNIT function
allows the flow unit of measure in which molbox1+ displays measured flow to be selected. These
include units of mass flow, including volumetrically based mass flow units (i.e., sccm) as wellas units of volume flow (i.e., ccm). See Table 29 for a complete listing of the unit conversions
available. molbox1+ can also display the measured flow in two different units of measure
simultaneously (see Section 3.4.6.5).
 OPERATION
If the molbox1+ is equipped with the optional MFC control function (see Section 3.4.8), the unit ofmeasure for the molbox1+ flow display may be defined by the currently selected MFC profile. In thatcase, the [UNIT] function key is used to select the MFC output display unit (see Section 3.4.8.3).
•

If an MFC profile other than profile #1 or #2 is active, the unit of measure is the unit ofmeasure selected in the MFC profile. If the MFC control function is not present, or isturned OFF, or MFC profile #1 or #2 is selected, the [UNIT] function key allows direct
selection of molbox1+ flow display units as described below.

•

From the main run screen, press [UNIT]:
1sccm 2slm 3uccm
4pccm 5mg/s 6vlm

The display is:

Select the desired unit. For all units except <uxxx> or <vlm>, operation then returns to the runscreen with the flow unit of measure changed to the selected unit. When user units (i.e., uxxx)
are selected, the reference temperature must be specified before the unit is activated (seeSection 3.4.3.3). When “vlm” (volume) units are selected, a menu of volume units isaccessed. The desired volume unit must be selected and then the temperature and pressureof the flowing gas must be specified (see Section 3.4.3.4).

Note•

If the MFC Control option is active and the MFC profile selected is NOT #1
or #2 (see Section 3.4.8), the molbox1+ flow unit is automatically the unit
specified in the current MFC profile (see Section 3.4.8 and 3.5.5) and the
UNIT function controls the unit used for displays of MFC set and measurevalues.

•See Section 7.1.3 for specific molbox1+ flow unit conversion calculations.

•molbox1+ supports many more flow units of measure than the six default
units of the UNIT function. The six units available under the UNIT function
can be customized to include any molbox1+ supported units in any order(see Section 3.5.8).

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3. OPERATION Caution
Many different types of flow units are commonly used including a wide
variety of mass flow units as well as volume flow units. Please read
Sections 3.4.3.1 through 3.4.3.4 for additional information on the various
unit definitions and how they are handled by molbox1+ before making unitof measure selections.

3.4.3.1

Mass Flow vs. Volume Flow
Note

COMPASS for molbox software users: conversions to volume(sometimes called actual) flow units are handled in COMPASS.
When using COMPASS, the molbox always operates in mass
flow units.
molbox1+ measures mass flow (quantity of material per quantity of time).
molbox1+ always calculates flow in terms of kg/second [kg/s]. It also supports
conversions of kg/second to a variety of other flow units. These include othermass flow units such as g/s and mole/s as well as volumetrically based mass
flow units (i.e., sccm and slm) (see Section 3.4.3.2). In steady state flow, mass
flow is the same at different points in the flow system independent of gas
pressure and temperature. Therefore, the measurement of mass flow made by
the molbloc/molbox represents the mass flow at the same time at other points ina steady state flow system.
molbox1+ can also make conversions to volume flow under specific pressure
and temperature conditions by dividing the mass flow by the density of the gas
under the specific pressure and temperature conditions (see Section 3.4.3.4).

Note
Volume flow is sometimes referred to as actual flow.
Volume flow is dependent on the actual temperature and pressure of theflowing gas at the point where volume flow is to be measured. Generally,
this point is not at the molbloc, it is at another point in the flow system (e.g., at the DUT).
At another point in the flow system, it is quite likely that the gas pressure andtemperature are different from the gas pressure and temperature at the molbloc.
Then, even in steady state flow conditions, the volume flow at the molbloc andthe volume flow at another point in the system are likely to be different.
Therefore, to accurately predict volume flow at another point in the system,
molbox1+ must calculate volume flow based on the gas pressure andtemperature at that other point, not at the molbloc. For this reason,
molbox1+ requires that gas pressure and temperature conditions at the DUT be
specified for volume flow measurements.
Estimating the flowing gas pressure and temperature at the point at which
volume flow is to be measured may be difficult.
The relevant gas pressure when measuring volume flow is the gas’s absolute pressure.
In cases in which the volume flow measurement is open to atmospheric (ambient)pressure, the volume flow pressure is atmospheric pressure. In other cases, there may
be ways to estimate the pressure at the volume flow measurement point but itprobably should be measured.
For temperature, if the volume flow measurement point is very near the molbloc,
one possibility is to use the molbloc temperature measurement. By design, themolbloc causes the temperature of the gas that flows through the molbloc to takeon the molbloc temperature. Therefore, the temperature of the gas as it exits the
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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

molbloc is the same as the molbloc temperature. If the volume flow measurement
point is not immediately downstream of the molbloc, the best estimate of gas
temperature is probably ambient temperature or the temperature of the device orbath used to stabilize gas temperature if one is present.

 Caution
Because volume flow (sometimes called actual flow) isdependent on gas pressure and temperature at the flow
measurement point, gas pressure and temperature must be
specified by the user when selecting volume flow units onmolbox1+. The measurement uncertainty (accuracy) in thevolume flow measurement is highly dependent on themeasurement
uncertainty
inthepressureandtemperature specified. Typically, temperature errors have aneffect on flow of about 0.35 %/°C and pressure errors have aneffect on flow of about 1%/kPa (6.8%/psi) if the DUT is used nearatmospheric pressure.

3.4.3.2

Volumetrically Based Mass Flow Unitsmolbox1+ supports a number of volumetrically based mass flow units ofmeasure. Volumetrically based mass flow units should not be confused withvolume or actual flow units (see Section 3.4.3.4). Volumetrically based mass
flow units define mass in terms of the quantity of gas that occupies a volume
under standard conditions of pressure and temperature. Since there is nouniversally accepted definition of standard conditions, molbox1+ supports thethree most common variances.
•Standard units (sxxx): The “s” prefix indicates standard. Volumetrically
based mass flow units preceded with the letter “s” (i.e., sccm, slm, scfh)
define standard conditions as pressure of 101.325 kPa absolute (14.6959
psia) and temperature of 0 °C (32 °F) and take into account the truecompressibility of the flowed gas.

•

User units (uxxx): The u prefix indicates user. This option is designed toprovide support for volumetrically based mass flow units with a reference
temperature other than 0 °C (see Section 3.4.3.3). Volumetrically basedmass flow units preceded with the letter “u” (i.e., uccm, ulm) define standard
conditions as pressure of 101.325 kPa (14.6959 psia) with the user
specifying the reference temperature. User units take into account the truecompressibility of the flowed gas.

•

Perfect units (pxxx): The “p” prefix indicates perfect. This option isdesigned to provide support for volumetrically based mass flow units thatassume ideal gas compressibility for all gases. Volumetrically based mass
flow units preceded with the letter “p” (i.e., pccm, plm) assume a gas
compressibility factor of 1 for all gases and define standard conditions aspressure of 101.325 kPa (14.6959 psia) and temperature of 0 °C (32 °F).

Note•

© 2010 Fluke Calibration

Volumetrically based mass flow units at reference
temperatures other than 0 °C (32 °F) can be defined using
user units (see Section 3.4.3.3).

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3. OPERATION•

3.4.3.3

In early 1996, SEMI (a semiconductor industry interest
group) adopted standard E12-96 which specifies that perfectunits be used for volumetrically based mass flow units. To
comply with the SEMI standard, pccm should be used rather
than sccm. To purchase a copy of the relevant SEMI
standard, contact SEMI at telephone 415.964.5111 or email
semihq@semi.org.

Volumetrically Based Mass Flow Units at Various
Reference Temperatures (UXXX)Units starting with the letter “u” (user units) are volumetrically based mass flow units(see Section 3.4.3.2) for which a reference temperature other than 0 °C is desired.
When a user unit is selected, the reference
temperature desired must be specified. Aftera user unit is selected, the display is:

Temperature ref?
0ºC

Enter the reference temperature desired for the volumetrically based mass flow
unit selected. The temperature unit can be changed between °C and °F by pressing[SETUP] and selecting <9tempU> (see Section 3.5.9). The temperature selected
applies to all the user units.

Note
Volumetrically based mass flow units, including user units (uxxx)
and perfect units (pxxx), are discussed further in Section 3.4.3.2.

3.4.3.4

Volume Flow Units (vlm)
Note

See Section 3.4.3.1 before using volume flow units.
flow is sometimes referred to as actual flow.

VolumeTo measure flow in volume flow units (sometimes referred to as actual flow
units), press [UNIT], <vlm> under the UNIT function. If <vlm> is not available,
see Section 3.4.3.5. This selection accesses the menu of volume units available.
Select the desired volume flow unit:
1.

Current volume flow pressure.

2.

Current volume flow temperature.
Indicates<bloc> if the current setting is to use the molbloc
temperature.

P:100.325 kPa T:20.1ºC
Edit P&T? 1No 2Yes

To retain the current volume flow pressure and temperature, select <1no> andoperation returns to the MAIN run screen with the selected volume flow unit
active. To change the volume flow pressure and/or temperature select <2yes>.
The next screen gives the choice of having
the volume flow gas temperature be either
the molbloc temperature or a user
specified temperature. If <2user> is selected,
a screen to enter the temperature is presented
before continuing. If <1molbloc> is selected,
will
thevolumeflow
temperature
automatically be taken as the molbloc
temperature.

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Gas temperature:
1molbloc 2user© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALThe next screen is to edit the volume flowpressure in the current pressure unit ofmeasure. Pressing [ENTER] accepts theedited value as the volume flow pressure andreturns to the MAIN run screen with theselected volume flow unit and gas
temperature and pressure active.

Volume unit gas pres101.325 kPa

Note
The temperature and pressure units of measure used to specify
volume flow conditions can be changed using [SETUP],<8presU> for pressure (see Section 3.5.8) and [SETUP],<9tempU> for temperature (see Section 3.5.9).

 Caution
Because volume flow is dependent on gas pressure andtemperature at the flow measurement point, gas pressure andtemperature must be specified by the user when selecting
volume flow units. The measurement uncertainty in the volume
flow measurement is highly dependent on the measurement
uncertainty in the pressure and temperature specified (seeSection 3.4.3.1).

3.4.3.5

Customizing FLOW Units Available Under The UNIT
Function

The UNIT function provides a choice of six different flow units of measure. The units
that are available by default are the six indicated in Section 3.4.3. However,molbox1+ supports many other units. These other units can be made available
for selection by customizing the UNIT function.
UNIT
function,Tocustomizethepress [SETUP] and select <7flowU>. The
display is:<#1> corresponds to the first of the six
available selections under the UNIT function.
Enter the number of the selection that you
would like to change. The display becomes:

Set up user unit #1

Flow unit type: 1std
2user 3perfect 4vlm

Select the flow unit type of the desired flow unit (see Table 29). Then select thedesired unit.
Table 29. Available Flow Units<1std><2user><1mol/s><2kg/s><3mg/s><4slm><5sccm><6scfm><7scfh><8slh><9sm3h>© 2010 Fluke Calibration<1ulm><2uccm><3ucfm><4ucfh><5um3h>Page 50<3perfect><1plm><2pccm><3pcfm><4pcfh><5plh><6pm3h><4vlm><1ccm><2lm><3lh><4m3h><6cfm><7cfh>

3. OPERATIONNote
The <4vlm> unit selection embeds the selection “vlm” into the
UNIT function rather than a specific volume unit. The “vlm”
selection provides access to all the volume flow units. In
summary the unit types are:<1std> (standard): mass flow units for which “standard”
conditions are temperature of 0 °C, standard atmosphere andusing the true compressibility factor of the gas.
<2user>: mass flow units for which “standard” conditions are auser settable temperature, standard atmosphere and using thetrue compressibility factor of the gas.
<3perfect>: mass flow units for which “standard” conditions aretemperature of 0 °C, standard atmosphere and assuming acompressibility factor of 1 for all gases.
<4vlm>: volume flow units.
See Sections 3.4.3.1 to 3.4.3.4 for additional information on flow
unit types.

3.4.4[TARE]

 PURPOSE[TARE] accesses five functions.
•

TARE function: To zero the molbox1+ differential pressure readings in molbloc-L
operation or verify the two RPTs by comparing them against each other in molbloc-S
mode (see Section 3.4.4.1).

•

PURGE function: To purge the molbloc connecting lines and molbox1+ internal volume of afirst gas with a second gas by flowing the second gas through the molbox1+ (see Section
3.4.4.2).

•

LEAK CHECK function: To check the molbox1+ internal pneumatic circuit and/or theexternal test circuit to which molbox1+ is connected, for leaks (see Section 3.4.4.3).

•

AUTOZ function: To periodically offset the molbox1+ RPTs relative to a reference
pressure value in order to compensate for possible changes in the RPT zero between fullrecalibrations (see Section 3.4.4.4).

•

BPR function (present only in molbloc-S operation): To measure and display themolbloc-S back pressure ratio (BPR) while operating in a BPR mode which does notcontinuously read and display BPR (see Section 3.4.4.5).

 OPERATION
Pressing [TARE] accesses a display with the choice of fourfunctions (five functions in molbloc-S operation). Select thedesired function. See the following for principles andoperation:

1tare 2purge
3leak check 4AutoZ ↓
5BPR

Note
Some screens (e.g., the Tare menu) may go beyond the two lines provided
by the display. This is indicated by a flashing arrow in the second line ofthe display. Press the [←] and [→] keys to move the cursor to access thelines that are NOT visible or directly enter the number of the hidden menu
choice if you know it.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

3.4.4.1<1Tare>The purpose and operation of the tare function is different for molbloc-L andmolbloc-S operation. It is described separately for the two modes below. The
molbox1+S does not support the ability to tare as it does not support laminar
molblocs.

3.4.4.1.1
molbloc-L Operation

PURPOSETo zero the molbox1+ at the molbloc operating pressure. Zeros the differential
reading between the two reference pressure transducers.


PRINCIPLE

The molbox1+ TARE function can be considered the equivalent of the zeroing
function performed on many instruments prior to making measurements.
molbox1+ calculates the flow through a molbloc-L from the differential pressure
across the molbloc. The differential pressure across the molbloc is measured bytaking the difference in the absolute pressure measured by the molbox1+’s twointernal RPTs. One RPT is connected to the upstream molbloc pressure port
and the other to the downstream molbloc pressure port.
If a common pressure is applied to both RPTs the differential pressure indicatedshould be zero. If a differential pressure value is observed, the value indicatedrepresents an offset in the differential measurement which will appear as anoffset or “zero error” on the flow through molbloc-L calculated by the molbox1+.
The TARE function allows the differential indication between the two RPTs to be
zeroed at the molbloc operating pressure to eliminate the zero error in differential
pressure measurement.
When the TARE function is activated, molbox1+’s internal valves operate topneumatically connect together the two absolute transducers at the molbloc
operating pressure (see Figure 5). The user can select whether this pressure is
the upstream or downstream molbloc pressure so that the tare can be made at
the pressure that will be held stable during operation (generally by a regulator or
because it is open to atmosphere). Activating the tare causes molbox1+ torecord the current differential as the tare value. The tare value is then used tocorrect all subsequent RPT readings. The tare value is the difference between
the two transducer readings (hi - lo). After taring, the upstream RPT is correctedby (- tare value/2) and the downstream RPT is corrected by (+ tare value/2).

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Closed
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 6. molbox1+ Internal Pneumatic Schematic –TARING CHANNEL A, UPSTREAM molbloc-L OPERATION© 2010 Fluke Calibration

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3. OPERATIONOPERATION

Note•

At a minimum, the TARE function should be executed
whenever the operating pressure of the molbloc is changed
significantly, at the beginning of each test or any time asignificant zero error is observed. For best results, it ispossible to tare before every reading since taring can be
executed while flowing. Best results will be obtained if theTARE function is executed with a stable flow through themolbloc.

•

If the molbox1+ is in A+B or A/B mode, the channel for which
to tare must be specified before taring.

To access the TARE function press [TARE], <1tare>.
Select tare pressure:
1upstream 2dnstream

The display is:

Selecting <1upstream> will tare the molbox1+ RPTs at the molbloc’s
upstream pressure (see Figure 5). Selecting <2dnstream> will tare the RPTs atthe molbloc’s downstream pressure (Low isolation valve open, High isolation
valve closed). Select the position where the pressure will remain the mostconstant during molbloc operation.
The next display is:1.

The current pressure read by the upstream (left)and downstream (right) RPTs without taking into
account the current tare value. These are untared
readings in the current pressure units.

2.

<T>, flashing, to indicate that this is a TARE display
showing the tare between the two absolute RPTs.

3.

The difference between the untared upstream anddownstream absolute pressure readings (upstream– downstream). This differential value is always inPascal [Pa].

4.

The flow corresponding to the current untared
differential pressure in the current flow units.

202.347 kPaa 202.311
T
36 Pa 0.06 sccm

This display allows the current untared absolute pressures and the resulting untared
differential pressure from the difference of the two absolute RPTs to be observed.
The flow value represents the current untared zero error in terms of flow. It does
not necessarily represent the current zero error on flow measurements as a tarevalue other than zero is probably already active.
Press [ENTER] when ready. molbox1+ makes measurements to determine a
new tare value. The next display is:1.

The tare value currently in use [Pa].

2.

The new tare value, resulting from this execution of
the TARE function [Pa].

OldT:
NewT:

44Pa
36Pa

Press [ENTER] to activate the new tare and return to the MAIN run screen.
Press [ESCAPE] to return to the [TARE] display without activating the new tare,leaving the old tare active.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALNote
The tare screen shows the upstream and downstream RPT
readings WITHOUT the current tare applied. The [P&T] screen
shows the RPT readings WITH the tare applied (see Section 3.4.5).
Limits and Errors
Excessively large tare values can diagnose molbox1+ RPT malfunction, the needto recalibrate or possible poor execution of the TARE function. To protect against
improper taring and to alert to possible RPT malfunction, molbox1+ checks thetare value before it is activated and displays warnings when appropriate. In themost extreme case, molbox1+ will not allow the tare value to be activated. The limits
checked and their consequences are as follows:
RPT coherence test: When attempting to activate a new tare, molbox1+ checks thecoherence between the two transducers and alerts the operator to excessive
disagreements. The test has two levels.
•

If the new tare is 200 Pa < tare < 3,000 Pa, a caution message is displayed.
Pressing [ENTER] overrides the caution and activates the new tare.
Pressing [ESCAPE] returns to the TARE screen.

•

If the new tare is > 3,000 Pa, the new tare cannot be activated.
Pressing [ENTER] or [ESCAPE] returns to the tare screen and retains theold tare. It is likely that molbox1+ needs service or a grossly incorrect
adjustment has been made to one or both of the RPTs.

Note
If a caution message appears or a tare cannot be activatedduring the taring process, repeat the taring process. If thecaution persists, the calibration of the RPT(s) should be verified(see Section 5.2). If the tare still cannot be activated, the RPT(s)should be recalibrated and molbox1+ may require other service.

3.4.4.1.2
molbloc-S operation

PURPOSETo check the molbox1+ RPT absolute pressure readings by comparing them at acommon molbloc-S upstream absolute pressure. Note that the taring function is
not supported by molbox1+S.


PRINCIPAL

When measuring the flow through molbloc-S, the critical pressure measured bymolbox1+ is the molbloc upstream pressure. The downstream pressure is only
monitored to be sure that critical flow conditions exist (see Section 3.1.5). To reduce
the uncertainty on the upstream pressure measurement, molbox1+ employs
internal valving to direct the upstream pressure to both RPTs, and the average ofthe two readings is used as the measured molbloc upstream pressure. To takeadvantage of this RPT averaging, the molbox1+ must be in either BPR OFF or
Auto BPR mode (see Section 3.6.9).
molbox1+ dynamically tares the two RPT readings when they are connected
together, so the user can view the “live” average pressure that is calculated and toallow smooth pressure and flow measurements during valve transitions in the Auto
BPR mode (see Section 3.6.9). RPT taring in molbloc-S operation occurs
automatically when needed and does not need to be initiated or performed by theuser.
The molbloc-S TARE function is available to allow the user to conveniently verify
that the two RPT measurements agree within an acceptable tolerance when acommon pressure is applied to them. When the TARE function is selected, the© 2010 Fluke Calibration

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3. OPERATION

molbox1+ internal valves operate to connect both Q-RPTs the active channel
UPSTREAM pressure port (see Figure 6). The RPT readings and the difference
between the two RPT readings (tare value) is displayed for evaluation by the user.
A message is also displayed in to indicate to the user whether the tare value is
acceptable, or indicates a need for pressure verification or calibration of the RPTs.
There is no need for the customer to save a new tare value in molbloc-S operation.
As in molbloc-L operation, the molbloc-S tare value is the difference between the
two transducer readings (hi - lo). In BPR modes where the tare value isdynamically calculated and applied, the upstream RPT is corrected by(- tare value/2) and the downstream RPT is corrected by (+ tare value/2).

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Closed
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 7. molbox1+ Internal Pneumatic Schematic –TARING CHANNEL A, molbloc-S OPERATIONOPERATION

To access the TARE function press [TARE], <1tare>. The display is:1.

The current pressure read by the upstream (left)and downstream (right) RPTs without taking into
account the current tare value. These are untared
readings in the current pressure units.

2.

<T>, to indicate that this is a TARE display showing
the tare between the two absolute RPTs.

3.

The difference between the untared upstream anddownstream absolute pressure readings (upstream– downstream). This differential value is always inPascal [Pa].

4.

Tare message

201.032 KpA ^201.013
T 19.3Pa
OK

For molbox1+ A350K:
<OK>
If
tare
is
less
than
50
Pa,
<CHECK> if tare is between 50 and 200 Pa<NEED CAL> if tare is greater than 200 Pa
For molbox1+ A700K:
<OK>
If
tare
is
less
than
120
Pa,
<CHECK> if tare is between 120 and,500 Pa<NEED CAL> if tare is greater than,500 kPa

Note
The tare screen shows the upstream and downstream RPT
readings WITHOUT the current tare applied. The [P&T] screen
shows the RPT readings WITH the tare applied (see Section 3.4.5).

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

3.4.4.2<2Purge>

PURPOSETo purge the lines between the molbloc and the molbox1+ and the internalmolbox1+ volumes of one gas with another gas by setting up a molbox1+ valving
configuration in which gas flows through the molbox1+. Note that the purge
function is not supported by molbox1+S.


PRINCIPAL

molbox1+ supports the measurement of flow of a variety of gases. To calculate theflow, the thermodynamic characteristics of the gas must be known. These are stored
in molbox1+ memory. For the flow to be calculated correctly, the gas flowing throughthe molbloc must be the gas that is selected on the molbox1+ (see Section 3.4.2).
When switching from the measurement of one gas to another, the old gas remaining
in the circuit and the new gas being flowed may mix for some time so that the gas
flowing through the molbloc is not purely the new gas. Erroneous measurements
may result. For this reason, it is important to purge the lines upstream anddownstream of the molbloc when changing gases. It is also important to purge themolbox1+ itself which, since there is normally no flow through it, may trap and holdthe old gas.
The PURGE function is designed to facilitate purging the molbox1+. It sets up themolbox1+ internal valving so that flow can pass through the molbox1+ (see Figure7). In this configuration, the lines between the molbloc and molbox1+ and themolbox1+ internal volume can be purged by simply flowing the new gas in thenormal flowing configuration. The flow resistance through the molbloc creates adifferential pressure which causes flow through the molbox1+ to occur, purging themolbox1+ with the new gas.

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Open
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 8. molbox1+
Internal Pneumatic Schematic – PURGING CHANNEL A



OPERATION

Note
For best results, the PURGE function should be executed
whenever the species of the gas flowing through the molbloc ischanged. Prior to activating the PURGE function, set flow throughthe molbloc to the highest rate that is practical. Then, with the gas
flowing, activate the PURGE function. Very small volumes of gas
remain trapped (deadended) in the molbox1+ in the PURGE
configuration. Therefore, it may be desirable to execute the
PURGE function more than once to clear these volumes by thepressure changes caused by PURGE execution.
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3. OPERATION

To access the PURGE function press [TARE],<2purge>. The display is:

Set purge time:
15 secThe purge time can be edited. Pressing [ENTER] causes molbox1+ to set its internal
valving to the purge configuration (see Figure 8) and go to the PURGE display:1.

The current pressure read by the upstream (left) anddownstream (right) RPTs in the current pressure unitof measure.

2.

<PURGING> to indicate that this is a PURGE display.

3.

Countdown of purge time remaining in seconds.

202.347 kPaa 202.311
PURGING
15 secmolbox1+ remains in the purge condition until the purge time countdown elapses.
It then automatically returns to normal operation. When the countdown elapses
operation returns to the run screen from which PURGE was accessed.
To interrupt the PURGE function, press [ESCAPE].

Note
The appropriate purge time setting is dependent on the flowrate and the volumes upstream and downstream of the molbloc.
Typically, 15 to 30 seconds is adequate. The time needed
increases as flow rates go down and volumes go up.

 Caution
When using the PURGE function, remember that the molbox1+
absolute RPTs are exposed to the pressure. Do not applypressure greater than,500 kPa (80 psi).

Note
If the molbox1+ is in A+B or A/B mode, the PURGE function
executes for the specified purge time for channel A and thenrepeats the purge sequence for channel B.

3.4.4.3
<3Leak Check>

PURPOSETo access the molbox LEAK CHECK and SYSTEM LEAK CHECK functions
which use molbox1+’s pressure and flow measurement capabilities to checkmolbox1+ and/or the system to which it is connected for leaks.


PRINCIPAL

molbox1+ is used both as a tool to accurately measure unknown flow values andas a calibration standard to calibrate other devices by comparison. Leaks within
the molbox1+ pneumatic circuit can cause erroneous flow measurements. Leaks inthe external flow circuit can cause the flow through the molbloc to be different
from the flow at another point in the system so that, even with an accurate
measurement and steady state flow, the molbox1+ indication is not an accurate
indication of flow at the other point in the system.
To obtain valid measurement results, it is important that leaks in molbox1+ and/or
the external flow system be identified and eliminated to the extent possible.
molbox1+ uses its precision on-board pressure and flow measurement
capabilities to help identify leaks with INTERNAL and EXTERNAL LEAKTESTING functions.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALOPERATION

Press [TARE] and select <3leak check> to access the LEAK CHECK functions.
Then select <1molbox> or <2system>.
<1molbox> is designed to leak check the internal molbox1+ pneumatic circuit.
<2system> is designed to leak check the system to which the molbloc/molbox
is connected.

Note
If the molbox1+ is in A+B or A/B mode, the molbloc channel (A or
B) to leak check must be specified prior to running the leak check.
Leak Check molbox


PURPOSETo check the internal molbox1+ pneumatic circuit for leaks.


PRINCIPAL

It is normally not necessary to run the MOLBOX LEAK CHECK procedure frequently.
It is intended for troubleshooting purposes when there appears to be a leak orother molbox1+ measurement problem whose source cannot be identified by the
SYSTEM LEAK CHECK or other troubleshooting means. It is recommended to run
the MOLBOX LEAK CHECK after it has been shipped or if it is suspected that themolbox has been exposed to a large shock or liquid or particulate contamination.


OPERATION

Press [TARE] and select <3leak check>, <1molbox>. The next display is:1.

The pressure read by the upstream transducer (left),the downstream transducer (right) and the pressure
unit of measure (middle).

2.

Indicator that the figure that follows is differential
pressure.

3.

Differential pressure across the molbloc in current
pressure unit of measure.

4.

Prompt for the action to take when ready.

347.458 kPaa 307.455
DP
40.003 <ENTER>

The molbox1+ internal valving is in its normal measuring configuration (see Figure 3).
This display is intended to assist the operator in setting the leak check pressure.
Apply the maximum differential pressure across the molbloc that is normallyencountered during flow measurement while working at your typical absoluteworking pressure. Neither pressure should be less than atmosphere. Use the <DP>indication on the molbox1+ display to set the absolute and differential pressure.
Once the pressure setting is correct, press[ENTER]. The molbox1+ actuates its internalvalves to isolate itself from the molbloc andtrap the upstream and downstream pressureson its RPTs (see Figure 8). The display is:

Vent molbloc<ENTER>

ports

Assure that both molbox1+ rear panel pressure connections are vented. Since
the pressure quick connections on the molbox1+ and the quick-connectors on themolbox1+ pressure connection tubes seal when disconnected, they cannot bevented by simply disconnecting them. The easiest way to assure that theconnections are vented is to maintain the normal connections to the molbloc,
shut off the molbloc gas source and open one or both ends of the molbloc so it
can vent to atmospheric pressure. Another alternative is to install the non-sealing
quick connectors (P/N 3068652) provided in the molbox accessories (see Section
2.1.2) into the molbox1+ quick connectors.

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3. OPERATION

1. Channel A High Isolation: Closed
2. Channel A Low Isolation: Closed
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: Closed

Figure 9. molbox1+
Internal Pneumatic Schematic - LEAK CHECK molbox CHANNEL A

Once the molbox1+ pressure connections are vented, press [ENTER].
1.

The pressure read by the upstream RPT (left), thedownstream RPT (right) and the pressure unit ofmeasure (middle).

2.

The ratio of the upstream RPT reading to thedownstream RPT reading.

3.

Leak check count down in seconds.

347.466 kPaa 35.459
1.03579:1 WAIT: 60

molbox1+ counts down for 60 seconds while monitoring the ratio of the twopressures and then determines whether an internal leak was present.
A significant leak in a pressure isolation valve or a bypass valve between the twochannels will cause the ratio between the two pressures to vary.
The molbox1+ LEAK CHECK function should
end with the prompt:

molbox passed theleak check

If any other prompt appears, repeat the process. If the leak check fails
consistently, note the failure message and contact a Fluke Calibration
Authorized Service Provider (see Section 7.4).
Leak Check System

PURPOSETo leak check the external system that is connected to the molbox1+.
PRINCIPAL

It is recommended to run the SYSTEM LEAK CHECK whenever critical physicalconnections in the system attached to the molbloc are broken and reconnected.
Critical connections are ones that are between the molbloc and the DUT, which,if they were to leak, would cause the flow through the molbloc and the DUT todiffer. Whenever a new DUT is connected to the system, it is a good idea to run
the SYSTEM LEAK CHECK.
The SYSTEM LEAK CHECK monitors changes in pressure in a closed systemdefined by the user to help determine whether a leak exists in the system. Oneof the ways a leak is detected is by monitoring pressure decay in the pressurizedclosed system. When the test volume is large, significant leaks may exist without
being detected because the pressure decay caused by the leak is reduced.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Therefore, the SYSTEM LEAK CHECK is most effective when the volume of theclosed system is minimized.
During molbloc-L operation, the SYSTEM LEAK CHECK also measures flow throughthe molbloc to help determine whether a leak is present upstream or downstream ofthe molbloc. Since molbloc-S is not capable of calculating meaningful flow values
with the very small differential pressure present during this test, the SYSTEM LEAKCHECK operates differently for molbloc-L and molbloc-S operation, as described inthe  OPERATION sections immediately below.

Note
The SYSTEM LEAK CHECK function uses molbox1+’s highprecision pressure and flow measurement capabilities to help
determine whether a leak exists in the system to which themolbloc is connected. This feature is to assist the operator inflow measurement and calibration. The system to which themolbloc is connected is the responsibility of the user. Failuresin the system leak check do not normally indicate defects in themolbox1+ or molbloc itself. The molbox1+ leak check is used to
identify molbox1+ failures.


OPERATION – molbloc-L Operation

To access the system leak check press [TARE] and select <3leak check>,<2system>. The display is:1.

The pressure read by the upstream RPT (left),the downstream RPT (right) and the pressure
unit of measure (middle).

347.589 kPaa 347.580<ENTER> when readyThis display is intended to assist the operator in setting the leak check pressure.
molbox1+ has actuated internal valves to connect the upstream and downstream
RPTs together, so they are both measuring an equal system pressure. (see Figure 9).

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Open
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 10. molbox1+ Internal Pneumatic Schematic- SYSTEM LEAK CHECK - CHECKING OFFSET AND STABILITY

Close an isolation valve downstream or plug the exhaust of the flow system thatis being tested (downstream of the molbloc anxxxxd the DUT if themolbloc/molbox is being used to test another device).
Using the molbox1+ display to read the pressure, set the pressure to the normal
operating pressure.
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3. OPERATIONNote
For systems with mass flow controllers (MFCs):
Keep in mind that the valves in most MFCs are not intended toprovide a complete gas shutoff and so they may not be suitable
to close off the test system. If an MFC is downstream of themolbloc and its downstream port is open to atmosphere, it isbest to close the system by connecting a cap to the MFC outlet
fitting or by connecting a shutoff valve downstream. If the MFC
valve is closed (most MFCs have normally closed valves) when
the operating pressure is applied from the upstream side, mostof the gas will be stopped by the MFC valve and will not
immediately fill the volume between the MFC valve and thedownstream cap or valve. If this happens, the gas may leak by
the MFC valve to fill this volume during the test and cause apressure decay and an apparent system leak. The solution is tosend a setpoint signal to the MFC to open the MFC valve whilepressurizing the system. Then close the MFC valve (remove thesetpoint signal) after the system is pressurized to avoid heatingof the test gas by the energized valve.
Next, close an isolation valve upstream of themolbloc so the gas supply is no longer open to
the system being checked. Once the pressure
has stabilized, press [ENTER]. The display is:347.587 kPaa 347.583
WAIT: 30

The molbox1+ is checking:•For pressure and temperature stability before running the system leak test•

That the disagreement between the two RPTs is not excessive

After 30 seconds, if the stability check is not passed, molbox1+ displays:•

If the pressure was not stable:

Leak is too large tocontinue•

If the molbloc temperature change was
too great:

Temp change was too
great to find leaks•

If the offset between the RPTs was
too great:

Offset excessive
check tare

If any of the above three prompts occurs, check the external system for leaks
and run the molbox1+ leak check before proceeding. If the tare was excessive,
tare the molbox1+ RPTs before running the leak check again (see Section 3.4.4.1).
Once the 30 second pressure stability/offset
check has been successfully completed,molbox1+ displays:

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347.587 kPaa 347.583
0.000 sccm [ENT]© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

When [ENTER] is pressed, molbox1+’s valves actuate to set up the system leakcheck configuration which is identical to the normal operating configuration(see Figure 3). The display becomes:
1.

Pressure read by the upstream RPT (left), thedownstream RPT (right) and the pressure unit ofmeasure (middle).

2.

Current measured flow.

3.

Time remaining in the leak check in seconds.

347.592 kPaa
0.101 sccm

47.58330

molbox1+ measures pressure and flow for a 40 second countdown. After thecountdown has elapsed, molbox1+ displays its conclusion from themeasurements. The display will be either:possible system
upstream leakOr
possible systemdownstream leak
Or
System passed systemleak check
Upstream and downstream refer to the possible location of the leak relative to theposition of the molbloc and the normal flow direction in the system. If you areunable to locate a leak in the flow path components, check or replace theupstream and downstream molbloc to molbox pressure tubes and their connectors
and retry the test. They are a critical part of the pneumatic system and if a significant
leak is present in these tubes, it will cause an error in flow measurement.


OPERATION – molbloc-S Operation

In molbloc-S operation, SYSTEM LEAK CHECK is a one-part test which tests forpressure decay in the closed system.
To access the system leak check press [TARE] and select <3leak check>,<2system>.
Leak check:
1run 2view

The display is:If <2view> is selected the test results screen (see below) is displayed with theresults from the most recent leak test.
To run the leak test, select <1run>.
molbox1+ actuates internal valves to connect the upstream and downstream
RPTs together, so they are both measuring an equal system pressure. (seeFigure 10).

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3. OPERATION

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Open
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 11. molbox1+ Internal Pneumatic Schematic- SYSTEM LEAK CHECK ON CHANNEL A - CHECKING OFFSET AND STABILITY

Close an isolation valve downstream or plug the exhaust of the flow system thatis being tested (downstream of the molbloc and the DUT if the molbloc/molbox isbeing used to test another device).
Open an isolation valve upstream of the molbloc to allow the working pressure topressurize the system.

Note
For systems with mass flow controllers (MFCs)
Keep in mind that the valves in most MFCs are not intended toprovide a complete gas shutoff and so they may not be suitable
to close off the test system. If an MFC is downstream of themolbloc and its downstream port is open to atmosphere, it isbest to close the system by connecting a cap to the MFC outlet
fitting or by connecting a shutoff valve downstream. If the MFC
valve is closed (most MFCs have normally closed valves) when
the operating pressure is applied from the upstream side, mostof the gas will be stopped by the MFC valve and will not
immediately fill the volume between the MFC valve and thedownstream cap or valve. If this happens, the gas may leak by
the MFC valve to fill this volume during the test and cause apressure decay and an apparent system leak. The solution is tosend a setpoint signal to the MFC to open the MFC valve whilepressurizing the system. Then close the MFC valve (remove thesetpoint signal) after the system is pressurized to avoid heatingof the test gas by the energized valve.
Next, close the isolation valve upstream of the molbloc so the gas supply is nolonger open to the system being checked. Once the pressure has had time to stabilize,press [ENTER].
ENTER to start
60 s leak check

The next display is:
Press [ENTER] to begin the test

Page 63© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALThe next display is:1.

The average pressure from the two molbox1+
RPTs.

2.

Current absolute pressure measurement in active
pressure unit of measure.

3.

SYSTEM LEAK CHECK count down in seconds.

199.167 kPa aleak testing 60s

Press [ESCAPE] to abort the leak test.
Pressing [ENTER] while the test is in progress restarts the test and reset the leaktest timer.
When the test is complete, a test results screen is displayed:
1.

The total change in average pressure over the test
interval.

2.

The currently selected pressure unit of measure.

3.

Average rate of pressure change, per second,
during the test.

∆P –0.0720 kPa
Rate –0.0012 kPa/s

Since flow systems using molbloc-S may use widely varying flow rates andtubing sizes, and test volumes may be quite large, it is difficult to predict whatsize pressure rate of change is acceptable to avoid significant flow errors. Your
best guide may be to run the SYSTEM LEAK CHECK often with your hardware,find a typical rate of change which represents a sound setup, and attempt tomatch that rate each time. In any case, you should be able to achieve a rate ofchange smaller than 0.01 % / second of the absolute line pressure.
If you observe a relatively large leak rate and are unable to locate a leak in the
flowpath components, check or replace the upstream and downstream molbloc tomolbox pressure tubes and their connectors and retry the test. They are a criticalpart of the pneumatic system and if a significant leak is present in these tubes,
it will cause an error in flow measurement.

3.4.4.4


<4AutoZ>

PURPOSETo offset the molbox1+ reference pressure transducers (RPTs) relative to areference value in order to compensate for possible changes in RPT zero
between full recalibrations.

 Caution© 2010 Fluke Calibration•

To assure operation within measurement uncertainty
specifications (see Section 1.2.2), it is recommended that
AutoZ be run (the value of Poffset updated) whenevermolbox1+ has been exposed to temperature changes
exceeding ± 15 ºC (36 ºF).

•

Improper use of the AutoZ function can cause out of
tolerance pressure measurements. AutoZ should be used
only by qualified personnel for the purpose of rezeroing themolbox1+ reference pressure transducer absolute pressure
measurement function.

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3. OPERATIONPRINCIPAL

AutoZ Purpose and Principle
The main component of the change over time of the molbox1+ RPTs is change inzero or offset, independent of span. Offsetting or “rezeroing” molbox1+ RPTs
relative to a reference between recalibrations allows measurement uncertainty
specifications to be maintained with less frequent full calibrations. The molbox1+
AutoZero function (AutoZ) provides full on-board support for the rezeroingprocess to simplify its application by the user.
The AutoZero function uses three values:
1. Pstd,0: The absolute pressure value indicated by the AutoZ reference, thedevice that is acting as the reference relative to which to offset the RPT.
The pressure at which AutoZ is performed is normally atmospheric pressure
and the Pstd,0 value can be supplied a) by manual entry, or b) automaticallyfrom a DHI RPMx Reference Pressure Monitor.
2. Pu,0: The absolute pressure reading of the RPT, with no AutoZ offset, at thetime AutoZ is performed.
3. Poffset: The difference between the absolute pressure reading of the RPTwith no AutoZ offset (Pu,0) and the indication of the AutoZ reference (Pstd,0):Poffset = Pu,0 - Pstd,0Poffset represents the change in zero of the RPT relative to the AutoZ standard(Pstd,0). The AutoZ function manages the determination, storage and application ofPoffset for both molbox1+ RPTs in absolute mode. The AutoZ handles both molbox1+
RPTs simultaneously as they are of the same range and always used together.
The source of Pstd,0 must be an absolute pressure, nominally atmosphericpressure, with uncertainty significantly better than that of the RPT that is being
AutoZeroed (see Section 1.2.2). This can be accomplished with a variety ofdigital barometers or with a piston gauge able to set absolute pressure.
When the RPTs are used with AutoZ ON, absolute pressure is calculated as:
Pabs = Pu,0 - Poffset
When RPTs are used with AutoZ OFF, Poffset is ignored.
When the RPT is calibrated, Poffset is set to zero. Poffset is then redetermined atregular intervals using the AutoZ function. The most recent value of Poffset isapplied to the RPT reading to correct for change in zero over time.
Recommendations for the Use of the AutoZ Function
The AutoZ function provides a powerful and easy to use tool for improving thestability over time of molbox1+ RPTs and maximizing the recalibration interval bycompensating for change in zero between full recalibrations. The following simple
recommendations will help assure that you use this feature to best advantage.
•

Always leave AutoZ ON when operating if the AutoZ routine has been run
regularly using a valid atmospheric reference.

•

Run AutoZ to update Poffset only when a reference whose measurement
uncertainty is known to be significantly better than that of the molbox1+
RPTs is available. Though it may not be practical and generally is notnecessary, the best possible reference with which to run AutoZ in absolutemeasurement mode is a gas operated piston gauge (such as a DHI PG7601)
applying an absolute pressure near atmospheric pressure to the molbox1+
test port. The best day to day reference is a properly calibrated DHI RPM4
with a BA100K RPT interfaced directly as an external device to the molbox1+
COM2 port.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL•

Allow the molbox1+ to stabilize at atmospheric pressure and ambient
temperature for 10 to 15 minutes before running AutoZ.

Note
If AutoZ is on, the AutoZ value will be applied while running thecalibration of molbox RPTs and an AutoZ indication is includedin the run calibration screen (See Section 5.2.4.1).


OPERATION

To access the molbox1+ AutoZ function press [TARE], <4AutoZ>. The display is:1.

Active RPT designator.

2.

Indication of whether AutoZ is currently ON or OFF
for this RPT and measurement mode.

1off 2view
3edit 4run•

Select <1off> (or <1on>) to change the AutoZ status.

•

Select <2view> to view the current values of Poffset for the two RPTs.

ON

Note
Poffset should be zero when the molbox1+ is new or has justbeen calibrated.
•

Select <3edit> to edit the values of Poffset.

Note
The value of Poffset is always displayed and entered in Pascal (Pa).
•

Select <4run> to run the AutoZ routine which determines and activates Poffset
values by measurement of Pstd,0 (see Section 3.4.4.4.2).

3.4.4.4.1

Edit AutoZ Caution

The edit AutoZ function should be used with great caution asentering inappropriate values and turning ON AutoZ may resultin out of tolerance measurements. In normal operation, thevalue of the AutoZ offset, Poffset, should be changed using therun AutoZ function (see Section 3.4.4.4.2). Before editing Poffset,
see Section 3.4..4.4, PRINCIPLE.
To edit the current Poffset values, press [TARE], <4AutoZ>, <3edit>. The display is:1.

Edit field for the value of Poffset of the upstream (1,Hi) RPT.

2.

Edit field for the value of Poffset of the downstream(2, Lo) RPT.

Poff:18.7 Pa
Poff:-3.5 Pa

UP1
DN2

Edit the Poffset value(s) as desired and press [ENT] to activate the new value(s).
Press [ESC] to abandon changes.

Note
The value of Poffset is always displayed and entered in Pascal (Pa).
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3. OPERATION

3.4.4.4.2

Run AutoZ

Run AutoZ is the function by which the current RPT reading is compared to areference, Pstd,0, at atmospheric pressure to determine a new value of Poffset.
The value of Poffset is then used by AutoZ to automatically correct the RPT for
possible change in zero over time (see Section 3.4.4.4, PRINCIPLE).
There are 3 program limits on the entry of Pstd,0 in place to reduce the possibilityof erroneous entries from either method, limits given in kPa absolute but directly
convertible to the current unit of measure:1) The entry must be within the limits of 70-110kPa absolute;2) If the entry is => 0.01% of nominal full scale from the current reading of either
RPT, the molbox1+ will warn that the value is high for the specifictransducer(s) but accept the entry;3) If the entry is => 0.02% of nominal full scale from the current reading of either
RPT, the molbox1+ will warn that the value is too high for the specifictransducer(s) and reject the entry;
In the case of 3), the pressure calibration of the molbox1+ RPT’s or the accuracy orcalibration of the pressure reference used to obtain Pstd,0 should be double-checked.
While an entry within the limits of 1) or 2) is acceptable, if running AutoZ results
in a value of Poffset that is greater than ± 0.005 % FS of the span of the RPT thatis being AutoZeroed, the RPT and/or the reference used as the source of Pstd,0
may be out of tolerance or the AutoZ process may have been faulty. Before
activating a new Poffset greater than ± 0.005 % FS of the active RPT, check to
be sure that both the RPT and the reference were in good working order,
properly vented to stable atmospheric pressure, at the same height, and readingin the same pressure units when AutoZ was run. A good laboratory practicewould be to keep a log of the resulting AutoZ Poffset values for the twotransducers over time to look for trends.
To access run AutoZ, press [TARE], <4AutoZ>, <4run>. The display is:1.

Selection of source of Pstd,0 reference fromwhich to AutoZ.

AutoZ by:
1Entry 2COM2

Selecting <1Entry> allows the value of Pstd,0 to be entered from the front panel keypad.
Selecting <2COM> allows the value of Pstd,0 to be read automatically from a DHI
RPMx connected to molbox1+’s COM2 communications port.
When AutoZ is run, the molbox1+ internal valves are actuated to connect bothmolbox1+ RPTs to the channel A, Hi port on the molbox1+ rear panel (see Figure
14 in Section 5.2.4.1). Be sure the channel A, Hi port is fully open to atmospherewhen running AutoZ. Note that the molbox1+ quick connectors and molbox1+ tomolbloc pressure lines are self sealing and therefore DO NOT open toatmosphere unless a quick connector stem is inserted. Use a quick connector stem
(DHI P/N 3068652, equivalent to Swagelok SS-QM2-S-200) supplied with themolbox1+ accessories to open the port to atmosphere.

Note•

Allow the molbox1+ to stabilize at atmospheric pressure
and ambient temperature for 10 to 15 minutes before
running AutoZ.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL•

If running AutoZ results in a value of Poffset that is greaterthan ± 0.005 % FS of the span of the RPT that is being
AutoZeroed, the RPT and/or the reference used as thesource of Pstd,0 may be out of tolerance or the AutoZ
process may have been faulty. Before activating a new
Poffset greater than ± 0.005 % FS of the active RPT, check to
be sure that both the RPT and the reference were in goodworking order, properly vented to stable atmosphericpressure, at the same height, and reading in the samepressure units when AutoZ was run.

•

When the run AutoZ selection is made, if a HEAD
correction is currently active (see Section 3.6.8) the headcorrection is momentarily disabled while running AutoZ toavoid “zeroing out” the head value.

•

The value of Poffset is always displayed and entered in
Pascal (Pa).

Run AutoZ by Entry
AutoZ by entry allows the value of Pstd,0 (see Section 3.4.4.4, PRINCIPLE) to beentered directly from the molbox1+ front panel. This provides a simple way of
AutoZeroing relative to an independent reference device such as a housebarometer that does not interface directly with molbox1+.
To access run AutoZ by entry press [TARE], <4AutoZ>, <4run>, <1Entry>.
The display is:1.

Real time reading (without head correction) of
upstream (1, Hi) RPT in unit of measure on line 2.

2.

Real time reading (without head correction) ofdownstream (2, Lo) RPT in unit of measure on line
2.

3.

Entry field for the value of Pstd,0. in the current
pressure unit of measure.

96.7715U
96.7778D
Pstd,0:96.7752 kPa

Enter the value of the AutoZ reference (Pstd,0) in the same unit of measure as thedisplay and press [ENT]. molbox1+ logs the readings and calculates a new
AutoZ offset value. The next display is:1.

Currently active/previous value of Poffset for the
upstream (1, Hi) RPT.

2.

Currently active/previous value of Poffset for thedownstream (2, Lo) RPT.

3.

New value of Poffset for the upstream (1, Hi) RPT for
the AutoZ that was just run.

4.

New value of Poffset for the downstream (2, Lo) RPT
for the AutoZ that was just run.

Old: 0.0 Pa 0.0
New: 3.7 Pa 2.6

Press [ENT] to activate the new values of Poffset or [ESC] to start over with entry
of a new AutoZ reference (Pstd,0) value.

Note
The value of Poffset is always in Pascal (Pa). The value of Pstd,0 isentered in the current pressure unit of measure.
Run AutoZ by COM2
AutoZ by COM2 allows a DHI RPMx Reference Pressure monitor connected to themolbox1+ COM2 to act as the AutoZ reference (source of Pstd,0) (see Section 3.4.4.4,
PRINCIPLE). The RPMx is read and the new Poffset is calculated automatically.
To access run AutoZ by COM2 press [TARE], <4AutoZ>, <4run>, <2COM2>.
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3. OPERATIONNote
For molbox1+ to communicate with an RPMx connected to its
COM2 port, the molbox1+ and the RPMx RS-232 interfaces must
be set up properly (see Section 3.6.6.1). If, the molbox1+ is unable
to locate an RPM ON COM2 when running AutoZ by COM2, it times
out after 6 seconds and displays an error message.
If molbox1+ is able to communicate with an RPMx on its COM2 port, the display is:1.

Real time reading (without head correction) of
upstream (1, Hi) RPT in unit of measure on line 2.

2.

Real time reading (without head correction) ofdownstream (2, Lo) RPT in unit of measure on line 2.

3.

Real time reading of the RPMx connected to molbox1+
COM2 to provide the value of AutoZ Poffset.

96.7715U
96.7778D
Pstd,0:96.7752 kPa

Observe the pressure outputs verify that they are stable. A 10 to 15 minute wait,
after venting, is recommended before running AutoZ. When ready, press [ENT]
to cause AutoZ to run. molbox1+ logs both RPT readings and calculates a new
AutoZ offset value. The display is:1.

Current/previous value of Poffset for the upstream(1, Hi) RPT.

2.

Current/previous value of Poffset for the downstream(2, Lo) RPT.

3.

New value of Poffset for the upstream (1, Hi) RPT for
the AutoZ that was just run.

4.

New value of Poffset for the downstream (2, Lo) RPT
for the AutoZ that was just run.

Old: 0.0 Pa 0.0
New: 3.7 Pa 2.6

Press [ENT] to activate the new values of Poffset or [ESC] to start over.

Note
The value of Poffset is always displayed and entered in Pascal (Pa).

3.4.4.5<5BPR> (molbloc-S Operation Only)

PURPOSETo quickly measure the molbloc-S upstream and downstream pressure andcalculate and display the BPR (back pressure ratio) when molbox1+ is in amolbloc-S BPR mode which would not otherwise measure the BPR.

Note
The <5BPR> menu selection is only present during molbloc-S
operation.


PRINCIPAL

molbox1+ uses the back pressure ratio, or BPR (the ratio of the molbloc-S
downstream absolute pressure to the upstream absolute pressure) to determine
whether the flow through the throat of the molbloc-S Venturi nozzle is critical andflow measurements within predictable uncertainty limits can be made withmolbloc-S (see Section 3.1.5). When operating molbox1+ with molbloc-S, theuser may select different BPR monitoring modes (see Section 3.6.9). Dependingon which BPR mode is selected, the BPR value is not always measured. The
BPR function allows the user to measure and display BPR directly at any time
regardless of which BPR mode is selected.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALOPERATION

Select [TARE], <5BPR>. The display is:1.

2.

The current pressure read by the upstream (left) anddownstream (right) RPTs without taking into accountthe current tare value. These are untared readings in
the current pressure unit of measure.

259.312 kPa ↓99.5769
BPR 0.38

The current BPR (ratio of downstream to upstream
absolute pressure).

Press [ENTER] or [ESCAPE] to exit the BPR function and return to the previous
RUN screen and BPR mode.

3.4.5[P&T] (Pressure and Temperature) PURPOSE
To provide continuous display of the pressures measured by molbox1+, the Reynolds
number of the flow through the molbloc, the temperature of the molbloc and other pressure
measurement information depending on whether the molbox1+ is used with molbloc-L or
molbloc-S.
 PRINCIPLE
molbox1+ continuously measures pressures and molbloc temperature and uses thesemeasurements to calculate flow.
The pressure at the molbloc upstream and downstream ports is read by two absolute
Reference Pressure Transducers (RPTs). In molbloc-L operation, the flow is calculated fromthe differential pressure across the molbloc. The differential pressure is calculated as thedifference between the two, tared (see Section 3.4.4.1.1), absolute RPTs (upstream downstream) and is displayed in the molbloc-L mode pressure screen.
In molbloc-S mode, the flow is calculated from the molbloc-S upstream pressure. The
upstream pressure may be read by either one or both of the RPTs, depending on which BPR
mode is in use (see Section 3.6.9). When the molbox1+ is in a valve state called BPR OFF,the molbloc-S downstream pressure is not measured and both RPTs are used to measure
the molbloc-S upstream pressure. Their readings are averaged to reduce the uncertainty ofthe molbloc-S upstream pressure measurement. An indicator is used next to the “downstream”
RPT value to show whether the RPT is currently measuring the molbloc downstream or
upstream pressure. Whenever the molbloc-S downstream pressure is measured, the BPR iscalculated and shown in the P&T pressure screen. When both RPTs measure the upstreampressure (BPR OFF mode), the indicated pressure for both RPTs is adjusted to equal theaverage of the two using the dynamic tare and BPR is no longer displayed.
Since the displays and operation of the P&T pressure screen are different for molbloc-L andmolbloc-S, they are described separately in Sections 3.4.5.1 and 3.4.5.2.
For temperature measurement, two Platinum Resistance Thermometers (PRTs) are embeddedin each molbloc. These are connected to the molbox1+ by the molbox1+ to molbloc cable.
The molbox1+ ohmic measurement system reads the resistance of the PRTs and calculates
molbloc temperature.
molbox1+ continuously calculates the Reynolds number of the flow through the molbloc.
The molbox1+’s current pressure and temperature readings as well as the Reynolds numberof the current flow can be displayed using the P&T function.

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3. OPERATION

3.4.5.1
molbloc-L Operation

OPERATION – molbloc-L Operation

Press [P&T] from any run screen. The display is:1.

Pressure read by the upstream RPT (left), thedownstream RPT (right) and the pressure unit ofmeasure (middle).

2.

The current differential pressure in the current
pressure unit of measure. <DP> indicates the value
is differential pressure.

3.

Current Reynolds number of the flow through themolbloc.

97.788 kPaa 97.783
DP 0.005
Re
0.02

Pressing [P&T] again or the [+/-] key toggles between the pressure screen andthe temperature screen:
1.

The average molbloc temperature in the current unitof measure (upstream + downstream/2).

2.

The temperature measured by the upstream molbloc
platinum resistance thermometer in the current unitof measure.

3.

21.82ºC

21.80ºC
21.78ºC

The temperature measured by the downstream
molbloc platinum resistance thermometer in thecurrent unit of measure.

To leave the P&T function and return to the MAIN run screen, press [ESCAPE].

Note
To change the pressure and/or temperature unit of measure,see Sections 3.5.8 and 3.5.9.

3.4.5.2

MOLBLOC-S operation



OPERATION – molbloc-S operation

1.

The current pressure read by the upstream (left) anddownstream (right) RPTs and the current pressure
unit of measure (middle). In BPR OFF or Automodes, tare is automatically applied to thesereadings. In BPR ON mode, tare is never applied.

2.

<h> indicates a head pressure correction is appliedor no character if no head correction.

3.

Arrow to indicate which pressure is being read by the“downstream” RPT. Down arrow indicates downstreampressure, Up arrow indicates upstream pressure.

4.

The current BPR (ratio of downstream to upstream
absolute pressure).

5.

Current Reynolds number.

259.312 kPah↓99.5769
BPR 0.38
Re 11039

Pressing [P&T] again or the [+/-] key toggles between the pressure screen andthe temperature screen:
1.

The average molbloc temperature in the current unitof measure (upstream + downstream/2).

2.

The temperature measured by the upstream molbloc
platinum resistance thermometer in the current unitof measure.

3.

The temperature measured by the downstream
molbloc platinum resistance thermometer in thecurrent unit of measure.

21.80ºC
21.82ºC
21.78ºC

To leave the P&T function and return to the MAIN run screen, press [ESCAPE].

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALNote
To change the pressure and/or temperature unit of measure,see Sections 3.5.8 and 3.5.9.

3.4.6[DISPLAY] PURPOSE
To select, from a variety of choices, the information that is displayed on the second line of themolbox1+ display. Averaging is one of the choices.
 PRINCIPLE
molbox1+ supports a variety of ADVANCED FLOW MEASUREMENT functions that are
displayed on the second (bottom) line of the molbox1+ display. In summary, the available
DISPLAY functions included are:
RATE:

Calculates and displays the current rate of change of flow in current flow
units/second (see Section 3.4.6.1). This function is a useful indication of thestability of the flow being measured. It is often used as an indication of positiveor negative leak rate and as a “go/no go” criterion for when to take data whencomparing molbox1+ and a DUT (e.g., in a calibration).

AVERAGE:

Calculates the average flow measurement over a user specified period of timeand displays the average, the standard deviation about the mean and acountdown in seconds to the next average (see Section 3.4.6.2). This function
is often used to filter out flow noise in an unstable system or to gather acorresponding sample when comparing molbloc/molbox measurements toanother device with a long integration time (e.g., a volumetric flow standard).
The magnitude of the noise is quantified by the standard deviation about themean. A second screen allows the instantaneous flow values to be viewed
during an averaging cycle.

HI/LO:

Records and displays the maximum and minimum flows measured since HI/LO
reset (see Section 3.4.6.3). This function is used to keep track of the minimum
and maximum flow observed over a period of time or to monitor whether a flow
min/max limit has been exceeded.

TOTAL:

Totalizes the mass or volume flowed over a period of time (see Section
3.4.6.4). Used to measure total mass or volume over a period of time. Can be
useful in calibration or verifying a totalizing flow device, when comparing
molbloc/molbox to a gravimetric standard or to add or remove a specificquantity of mass or volume from a system.

UNIT:

Displays the measurement of flow through the molbloc simultaneously in asecond flow unit (see Section 3.4.6.5). This function is convenient whenworking with an unfamiliar flow unit of measure to simultaneously display afamiliar unit or any time a real time flow unit conversion is desired.

DEVIATION: Continuously calculates and displays the deviation between the current flow
measured by molbox1+ and a target flow defined by the user (deviation =current flow - target) (see Section 3.4.6.6). This function is useful in monitoring
the evolution of flow around and/or away from a desired set point.
FREEZE:

Captures and displays the instantaneous flow value measured by molbox1+
when the [ENTER] key is pressed (see Section 3.4.6.7). This function is usefulto record the flow present at the time of an operator observed trigger event.

CLEAN:

Blanks out the second line of the display (see Section 3.4.6.8). This function isused when a simple display of flow measured by the molbox1+, without
additional information, is desired.

© 2010 Fluke Calibration

Page 72

3. OPERATION

 OPERATIONTo select a DISPLAY function, press [DISPLAY] from the MAIN run screen.
1avg 2rate 3hi/lo
The display is:

4total 5unit 6dev
7freeze 8clean↓

The cursor is on the active DISPLAY function. Selecting a DISPLAY function returns to the
MAIN run screen with the selected function active.
See Section 3.4.6, PRINCIPLE for a summary of DISPLAY functions and Sections 3.4.6.1
through 3.4.6.8 for detailed information on each DISPLAY function.

Note•

In molbloc-S operation, at times, the back pressure ratio, BPR, will be
too high for molbox1+ to calculate a meaningful flow value. When thisoccurs, the top line of the run screen display always reads <BPR HI>
and the bottom line shows the label <BPR> and the current measured
BPR value. This display has priority over the appearance of the display
functions described in this section, but the display will return to normalwhen the BPR returns to a usable level for molbloc-S measurements(see Section 3.1.5).

•

The default DISPLAY function is RATE which causes the second line of thedisplay to show <R> followed by the current rate of change of flow incurrent flow unit of measure per second (see Section 3.4.6.1).

3.4.6.1<1Rate>PURPOSETo activate the RATE DISPLAY.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the RATE DISPLAY press [DISPLAY] and select <1rate>. Selecting <1rate>
returns to the MAIN run screen with the RATE DISPLAY active.
With the RATE DISPLAY active, the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Current rate of change of flow in current flow unit ofmeasure per second.

* 101.27 sccm
R 0.03/sec

N20

Note
•

The RATE DISPLAY is different and separate from thestability setting which is used to set the stability criterion onwhich the Ready/Not Ready indication is based (seeSections 3.1.3, 3.5.2). The RATE DISPLAY only causes thecurrent rate of change to be displayed and has NO affect on
the stability setting or the Ready/Not Ready condition.

•

To go to a DISPLAY other than RATE, press [DISPLAY] andmake a new DISPLAY choice.
Page 73© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

3.4.6.2
<2Avg> (Average)

PURPOSETo activate the AVERAGE DISPLAY and/or adjust the period of time over which
averaging occurs.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To access the AVERAGE DISPLAY, press [DISPLAY] and select <2avg>.
The display is:1.

Edit field for averaging period in seconds. Default is
20. Minimum 3, maximum 999.

Averaging Period:
20 s

Edit the averaging time period if desired. Pressing [ENTER] returns to the MAIN
run screen with the AVERAGE DISPLAY active.
With the AVERAGE DISPLAY active the MAIN run screen is:
1.

Average flow measured over last completed
averaging period.

2.

Standard deviation of last completed
averaging period.

3.

Countdown in seconds until completion of on-goingaveraging period.

* 101.99 sccm
N20
δ 0.0618 secThe AVERAGE DISPLAY has a second screen that allows the instantaneous
flow readings to be viewed while an averaging cycle is running. This screen isavailable only if the molbox1+ MFC control option is NOT present or OFF. If themolbox1+ MFC control option is not present or OFF, pressing [+/-] toggles
between the MAIN run AVERAGE screen and the instantaneous values
AVERAGE screen. If the molbox1+ MFC control option is ON, pressing [+/-]
accesses the MFC averaging screens. The MFC averaging screens are theequivalent of the normal MFC screens but the values are averaged for the
averaging time. The instantaneous AVERAGE screen is:1.

Instantaneous flow value
normal integration rate.

2.

Countdown in seconds until completion of ongoing averaging period.

3.

Current rate of change of flow in flow unit ofmeasure/second..

3.4.6.3
atmolbox1+’s<3 Hi/Lo>PURPOSETo activate the HI/LO DISPLAY.

Note
See Section 3.4.6, PRINCIPLE.

© 2010 Fluke Calibration

Page 74* 101.59 sccm
N20
R 0.0025
18 sec

3. OPERATIONOPERATION

To activate the HI/LO DISPLAY press [DISPLAY] and select <3hi/lo>. Selecting<3hi/lo> resets the HI/LO values and returns to the MAIN run screen with the
HI/LO DISPLAY active.
With the HI/LO DISPLAY active, the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Highest flow observed since HI/LO reset.

3.

Lowest flow observed since HI/LO reset.

* 101.22 sccm
N20
H 101.44
L99.113

The HI/LO values change each time a new HI or LO flow value occurs.
The HI/LO record can be reset at any time by pressing [ENTER] allowing a
HI/LO reset without going back through the DISPLAY menu.

Note•

When DISPLAY is set to HI/LO, the MFC indicator of theoptional MFC function is not included on the second line of
the molbox1+ display as the HI/LO DISPLAY occupies theentire second line of the molbox1+ display (see Section
3.4.8).

•The set point of the optional MFC function cannot bechanged in the HI/LO display because [ENTER] is used by
the DISPLAY function. MFC set point can only be entered in
the RATE, UNIT or CLEAN DISPLAY functions.

•

Changing the flow unit of measure, the gas, the K factor or
running a TARE function while in HI/LO resets the HI/LO
record.

•To go to a DISPLAY other than HI/LO, press [DISPLAY] andmake a new DISPLAY choice.

3.4.6.4<4Total> (Totalizer)

PURPOSETo activate the TOTALIZER DISPLAY.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the TOTALIZER DISPLAY, press [DISPLAY] and select <4total>.
The display is:1.

Edit field for time over which to totalize (hh:mm:ss).
Default period is 00:10:00; maximum 99:59:59.

Totalizing period:
00:10:00

Edit the totalizing period as desired. Pressing [ENTER] returns to the MAIN run
screen with the TOTALIZER DISPLAY active.

Page 75© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALWith the TOTALIZER DISPLAY active the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Total mass or volume accumulated over elapsed
totalizing run time.

3.

Units of measure of mass or volume (derived from thecurrent flow unit) of the totalized value (see Table 22).
The units of measure are not shown if the screen spaceis needed to show a large totalized value.

4.

* 101.45 sccm
Σ0.00 scc

N20

00:00:00

Elapsed totalizing time (hh:mm:ss). Always starts fromzero and counts up until totalizing period elapses.

Press [ENTER] to start totalizing. The elapsed time counter starts and the total
mass or volume begins to accumulate. Totalizing continues until the set totalize
period is complete. When the totalizing period is complete, molbox1+ sounds
three beeps and displays the totalizing complete screen in which the total flow orvolume and elapsed totalizing time are frozen with totalizing time NOT flashing.
To start a new totalizing run from the totalizing complete screen, press [ENTER].
This clears the previous total, resets to the totalizing timer and starts totalizing.

Note© 2010 Fluke Calibration•

When DISPLAY is set to TOTALIZE, the MFC indicator of theoptional MFC function is not included on the second line of
the molbox1+ display as the TOTALIZE DISPLAY occupies
the entire second line of the molbox1+ display (see Section
3.4.8).

•The set point of the optional MFC function cannot bechanged in the TOTALIZE display because [ENTER] is usedby the DISPLAY function. MFC set point can only be enteredin the RATE, UNIT or CLEAN DISPLAY functions.

•

To view a split total and/or to start a new totalizing run with a
new run time, press [ENTER] while totalizing (see Viewing a
Split Total and/or Starting a New Totalizing Run with a New
Run Time of this section). To change totalizing run time anyother time, press [DISPLAY] and select <4total>.

•

Certain functions cannot be executed while totalizing. These
functions include change K, change gas, change flow unit ofmeasure, tare. If <Access restricted while totalizing> isdisplayed when a function key is pressed during totalizing,
the function is one that cannot be executed while totalizing.
To execute the function, abort the totalizing run or wait until
after the run has completed. This feature is to avoid
accidentally aborting or corrupting a totalizing run.

•To set a new totalizing time without going back through the[DISPLAY] menu, press [ENTER] and select <2new> from the
TOTALIZER screen. To freeze a split total without stopping
the totalizing run, press [ENTER] or [ESCAPE] while
totalizing (see Viewing a Split Total and/or Starting a New
Totalizing Run with a New Run Time below in this section).

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3. OPERATION

Table 30. Flow Units and Corresponding Total Mass or Volume Units

3.4.6.5


FLOW UNITTOTAL MASS OR
VOLUME UNIT

mol/s

mol

kg/s

kg

mg/s

mg

slh or slm

sl

sccm

scc

scfh or scfm

scf

Ulm

ul

Uccm

ucc

ucfm or ucfh

ucf

plm or plh

pl

pccm

pcc

pcfm or pcfh

pcf

lm or lh

l

ccm

cc

m3m or m3h

m3

cfm or cfh

cf<5Unit>PURPOSETo activate the UNIT DISPLAY.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the UNIT DISPLAY, press [DISPLAY] and select <5unit>. The unitof measure that will be used for the second line of the MAIN run screen display
must then be selected. The unit selection process is identical to that of the[UNIT] function key (see Section 3.4.3). Once the unit has been selected
operation returns to the MAIN run screen with the UNIT DISPLAY active.
With the UNIT DISPLAY active the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Flow equivalent of the current measured flow in thealternate flow unit of measure.

3.

Alternate flow unit of measure selected in UNITDISPLAY.

* 101.27 sccm
= 0.1013 slm

N20 Caution
The reference temperature setting for the user units (i.e., uccm
and ulm) (see Section 3.4.3.3) and the temperature and pressure
settings for volume units (see Section 3.4.3.4) apply to the units
in the main UNIT selections as well as the UNIT DISPLAY
selection. Therefore, it is not possible to simultaneously display
user units or volume units with different reference temperatures
Page 77© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

and/or pressures. When you change the temperature orpressure setting for one type of unit, you change it for that typeof unit wherever it is used. It is possible to show the difference
between volumetrically based mass flow units at 0 °C andanother temperature by choosing the “s” version (e.g., sccm)
for 0 °C as the main unit and a user unit with a different
reference temperature as the UNIT DISPLAY, or vice-versa.

Note
To go to a DISPLAY other than UNIT, press [DISPLAY] and makea new DISPLAY choice.

3.4.6.6<6Deviation>

PURPOSETo activate the DEVIATION DISPLAY and/or edit the deviation target.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the DEVIATION DISPLAY, press [DISPLAY] and select <6dev>.
The display is:1.

Edit field to edit the target value from which thedeviations is to be measured.

Target:100.00 sccm

Edit the desired target value. Pressing [ENTER] returns to the MAIN run screenwith DEVIATION DISPLAY active using the entered target value.
With the DEVIATION DISPLAY active the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Target value in current flow unit of measure.

3.

Deviation of current flow from target value in % ofreading.

* 100.53 sccm
N20
D 0.53 %T 100.00

Note•

Pressing [ENTER] from the MAIN run screen when the
DEVIATION DISPLAY is active goes directly to the target
editing screen. This allows the target value to be changed
without going through the DISPLAY menu.

•

The DEVIATION DISPLAY target value is the value fromwhich % deviations (D) are measured by the DEVIATIONDISPLAY following:
D = (current flow – target) x 100
target•© 2010 Fluke Calibration

To go to a DISPLAY other than DEVIATION, press[DISPLAY] and make a new DISPLAY choice.

Page 78

3. OPERATIONPURPOSETo activate the DEVIATION DISPLAY and/or edit the deviation target.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the DEVIATION DISPLAY, press [DISPLAY] and select <6dev>.
The display is:1.

Edit field to edit the target value from which thedeviations is to be measured.

Target:100.00 sccm

Edit the desired target value. Pressing [ENTER] returns to the MAIN run screenwith DEVIATION DISPLAY active using the entered target value.
With the DEVIATION DISPLAY active the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Target value in current flow unit of measure.

3.

Deviation of current flow from target value in current
flow unit of measure.

* 100.53 sccm
N20
D 0.53
T 100.00

Note•

When DISPLAY is set to DEVIATION, the MFC indicator of theoptional MFC function is not included on the second line of
the molbox1+ display as the DEVIATION DISPLAY occupies
the entire second line of the molbox1+ display (see Section
3.4.8).

•The set point of the optional MFC function cannot bechanged in the DEVIATION display because [ENTER] is usedby the DISPLAY function. MFC set point can only be enteredin the RATE, UNIT or CLEAN DISPLAY functions.

•

Pressing [ENTER] from the MAIN run screen when the
DEVIATION DISPLAY is active goes directly to the target
editing screen. This allows the target value to be changed
without going through the DISPLAY menu.

•

The DEVIATION DISPLAY target value is the value fromwhich deviations (D) are measured by the DEVIATIONDISPLAY following:D = current flow - target•

If the flow unit is changed while the DEVIATION DISPLAY is
active, the target value remains at the same numerical value.
It is not converted to the new unit.

•

To go to a DISPLAY other than DEVIATION, press [DISPLAY]
and make a new DISPLAY choice.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

3.4.6.7


<7Freeze>

PURPOSETo activate the FREEZE DISPLAY.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the FREEZE DISPLAY press [DISPLAY] and select <7freeze>.
Selecting <7freeze> returns to the MAIN run screen with the FREEZE DISPLAY active.
With the FREEZE DISPLAY active, the MAIN run screen is:1.

Standard MAIN run screen top line.

2.

Flow measured in the current flow units when
[ENTER] was pressed (displays 0.00 by default
when FREEZE DISPLAY is first activated).

* 101.75 sccm
F 99.24

N20

Pressing [ENTER] causes the current flow measured by the active molbox1+
range to be captured and displayed.

Note•

If the flow measurement unit is changed while the FREEZEDISPLAY is active, the FREEZE value defaults back to zero.

•

The set point of the optional MFC function cannot bechanged in the FREEZE display because [ENTER] is used by
the DISPLAY function. MFC set point can only be entered in
the RATE, UNIT or CLEAN DISPLAY functions.

•

To go to a DISPLAY other than FREEZE, press [DISPLAY]
and make a new DISPLAY choice.

3.4.6.8<8Clean>PURPOSETo activate the CLEAN DISPLAY.

Note
See Section 3.4.6, PRINCIPLE.
OPERATION

To activate the CLEAN DISPLAY press [DISPLAY] and select <8clean>.
Selecting <8clean> returns to the MAIN run screen with the CLEAN DISPLAY active.
With the CLEAN DISPLAY active, the MAIN run screen is:© 2010 Fluke Calibration

1.

Standard MAIN run screen top line.

2.

“Clean” second line.

Page 80* 101.45 sccm

N2O

3. OPERATION

Note

3.4.7

•

The MFC indicator is not included in the MAIN run screen in
the CLEAN DISPLAY function (see Section 3.4.8).

•

To go to a DISPLAY other than CLEAN, press [DISPLAY] andmake a new DISPLAY choice.

[A/B] PURPOSE
To switch the active molbloc channel between channel A and channel B.
 PRINCIPLE
See Section 3.1.1
 OPERATION
Pressing the [A/B] key changes the active molbloc channel. The currently active channel isindicated by the lit RED LED below the molbox1+ front panel display. When the A/B function
is operated, molbox1+ actuates internal valves to change the molbloc channel that isconnected to the molbox1+’s internal pressure transducers. Pressing the [A/B] key alsoaborts any A_B mode that may be active (see Section 3.5.4).

Note
When channels are changed using the A/B function, the molbloc is notinitialized by the molbox1+. When the molbloc connected to a channel ischanged, use <1molbloc> in the SETUP menu (see Section 3.5.1) toreinitialize. This will cause the molbox1+ to read and store the molbloc
EEPROM information and assure that the newly connected molbloc isproperly identified and used.
Channels, Functions and Settings
In general, molbox1+ functions and settings are channel specific. They are set and storedindividually for each channel so that changing settings for one channel does not change thesetting for the other.
The only functions and settings that are NOT channel specific are:Functions:[MFC], [DISPLAY]

Setup Menu:<3adj>

Special Menu: <9BPR>

3.4.8[MFC](Optional)

 PURPOSE
To turn the analog MFC control function ON and OFF and to select an MFC profile to be used
when the MFC function is ON.

Note
The MFC control function is an optional feature of molbox1+ that allows
setting and reading an external MFC with analog voltage or current
signals. If the molbox1+ does not include the MFC control function, [MFC]
has no function.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL OPERATION
When [MFC]
the operator:isfirst pressedthescreenprompts

SELECT MFC CHANNEL(0 DISABLES): 0

The MFC channel refers to the channel of the optional MFC switchbox that can bepurchased as an accessory to molbox1+ to allow the MFC control function to be switchedbetween up to five MFCs. Entering [0] disables the MFC control function. Entering [1], [2],[3], [4] or [5] enables the MFC function and selects the corresponding channel on the MFC
switchbox. If an MFC switchbox is not being used, select channel #1 when activating the
MFC function.
SELECT PROFILE#3

The operator is then prompted:

The number refers to the MFC profile number (see Sections 3.4.8.2, 3.5.5). Edit the profile
number to the desired profile. When the profile number is entered, a summary of the profile
is displayed. When [ENTER] is pressed again, the display returns to the MAIN run screen
and the MFC function is active using the profile selected. <MFC> or <MFM> (depending on
the device type of the selected profile) and the active channel number may be displayed in
the bottom right hand corner of the MAIN run screen depending on the current display mode(see Section 3.4.6).
When the MFC function is ON, pressing [ENTER] from the MAIN run screen or an MFC run
screen allows entry and execution of the MFC set point command. When the DISPLAY
MODE is AVERAGE, HI/LO, TOTAL, DEVIATION or FREEZE, [ENTER] is used for the
DISPLAY MODE (see Section 3.4.6). MFC set point commands cannot be entered in these
DISPLAY MODES. MFC set points can only be entered in the RATE, UNIT and CLEANDISPLAY MODES.

Note•

To [ENTER] MFC set point, the DISPLAY MODE must be RATE, UNIT or
CLEAN. In other DISPLAY MODES, [ENTER] is used by the DISPLAY
MODE.

•

Pressing the [] arrow key any time the MFC control function is active
causes an instant display of the current MFC profile summary allowing aquick check of the characteristics of the currently active MFC profile.
Pressing [ESCAPE] returns from MFC profile screen to the last run screen.

3.4.8.1

MFC Run Screens

When the MFC function is ON, the MAIN run screen is unchanged but <MFC> or<MFM> and the active MFC channel number are shown in the bottom right handcorner of the molbox1+ display (in RATE, UNIT and FREEZE DISPLAY modes only,
see Section 3.4.6). Two or three, depending on the MFC profile in use, special
MFC run screens can be accessed by pressing the [+/-] key. When the [+/-] key
is pressed from the first MAIN run screen, the first MFC run screen is displayed:© 2010 Fluke Calibration

1.

Ready/not ready indication.

2.

Flow value and flow unit of the flow through the active
molbloc as read by the molbox1+.

3.

The gas that is currently being flowed through theactive molbloc.

4.

MFC set point set by the molbox1+.

5.

MFC output measured by the molbox1+.

6.

Unit of measure of MFC setpoint and output (V, mA,% FS or blank if flow units).

Page 82* 101.001 sccm N2
S1.020 M1.03 V

3. OPERATION

Pressing [+/-] from the first MFC run screen causes the second MFC run screen
to be displayed (this screen is not present when MFC profile #1 or #2 is being
used, see Section 3.4.8.2, 3.5.5):
1.

Ready/not ready indication.

2.

Flow value and flow unit of the flow through the active
molbloc as calculated by the molbox1+.

3.

The gas that is currently being flowed through theactive molbloc.

4.

The MFC measurement error in % calculate as MFC − molbox1
 •100 MFC F.S. * 101.001 sccm N2
E 0.85% F.S.

Pressing [+/-] from the second MFC run screen causes the third MFC run screen
to be displayed (this is the second screen if MFC profile #1 or #2 is in use, see
Section 3.4.8.2, 3.5.5).
1.

Positive MFC supply voltage.

2.

Negative MFC supply voltage.

3.

Current MFC valve voltage.

4.

Current MFC set point.

+ 15.11 V
S1.020 V-15.15V
11.29V

Summary
Pressing [+/-] toggles the run screens from the MAIN run screen through the
MFC run screens and back to the MAIN run screen.

3.4.8.2

MFC Profiles

MFC profiles are used by molbox1+ to configure the MFC function. MFC profiles
define the analog signal range of the MFC and the relationship between theanalog signal range and the flow range of the MFC. This information allows
molbox1+ to operate with the correct signal for the current MFC and to convert
the MFC analog signals to the corresponding flow or % FS values when desired.
MFC profiles are created and edited in [SETUP], <5MFC> (see Section 3.5.5).

3.4.8.3

Units of Measure When Using the MFC Control
OptionWhen the MFC function is active, the molbox1+ flow units of measure are always
the units of measure specified in the active MFC profile.
When the MFC function is active, unless the profile is #1 or #2, the flow unit ofmeasure in which the flow through the molbloc is displayed is determined by theflow unit of measure in the MFC profile. The [UNIT] function key is for selectionof the unit of measure of the MFC setpoint and output. The choices available are
V or mA (depending on the active MFC profile's analog range), % FS or flow.
The % FS selection causes MFC setpoint and output to be displayed in % FS of
the MFC which molbox1+ calculates using the definition of analog range and flow
range contained in the MFC profile. The flow unit selection causes MFC setpoint
and output to be displayed in the flow units of the MFC calculated using thedefinition of analog range, flow range and flow units contained in the MFC profile.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Note
MFC profiles #1 and #2 are default profiles for working with the
MFC function directly in analog units without an MFC flow range
or units. Profile #1 is 0 to 5 V, profile #2 is 4 to 20 mA. When the
MFC function is active with profile #1 or #2 selected, the MFC
units of measure are always V (profile #1) or mA (profile #2). The
UNIT function selects the molbox1+ flow measurement unit.

3.4.9

[RES]

 PURPOSE
To set the resolution of molbox1+’s display of the flow through the molbloc and other flow
display and entry values.
 PRINCIPLE
The resolution with which the flow measured by molbox1+ is displayed can be adjusted. Thisfeature can be used to reduce the resolution when lower precision measurements are being
made and additional digits might confuse or distract the operator.
The resolution setting determines the number of digits with which flow is displayed. The desired
resolution is calculated based on the nominal full scale range of the molbloc in the current gas
and flow unit of measure and then rounded to the furthest digit to the right (i.e., resolution of 0.001% on a 100 sccm molbloc is 0.001 sccm).

Note
The default molbox1+ display resolution setting is 0.001 % of molbloc FS.
The RES setting does not affect the resolution of flow informationtransmitted remotely.
Remote information always has maximum
resolution of 0.0001 % of molbloc FS.
 OPERATION
To access the resolution function press [RES].
Press the [←] to decrease the resolution and [→] to increase the resolution. Each presschanges the resolution by a factor of 10. Once the desired resolution is displayed, press[ENTER] to set the selected resolution and return to the main run screen.

Note
The resolution setting affects the display of the measured flow as well asother indications and settings (i.e., quantities shown by the [DISPLAY]
functions).

3.5[SETUP] PURPOSE
The [SETUP] key accesses a menu of commonly used molbox1+ functions and features that do NOT
have direct function keys. These functions include:<1molbloc> To initialize a molbloc when it is connected to molbox1+ and/or to identify the molblocs
currently connected to molbox1+ (see Section 3.5.1).
<2stab>To change the stability limit that serves as the criterion for the flow Ready/Not Ready
indication (see Sections 3.5.2 and 3.1.3).

<3adj>To set an adder and multiplier to adjust molbox1+ flow readings (see Section 3.5.3).

© 2010 Fluke Calibration

Page 84

3. OPERATION<4A_B>To set molbox1+ flow measurement modes that use the combination of two molblocs onchannels A and B to measure flow (see Section 3.5.4).

<5MFC>

To create, store and edit the MFC profiles used by the optional MFC function (see Sections
3.5.5 and 3.4.8).

<6reg>

To turn regulation mode of the optional MFC function ON and OFF and to set the regulation
period for the regulation mode (see Section 3.5.6).

<7flowU>

To customize the flow unit choices available under [UNIT] (see Sections 3.5.7 and 3.4.3).

<8presU>

To select/change the unit of measure in which molbox1+ displays pressure values(see Section 3.5.8).

<9tempU>

To select/change the unit of measure in which molbox1+ displays temperature values(see Section 3.5.9).

 OPERATION
1molbloc 2stab 3adj
To access the SETUP menu, press [SETUP] from the MAIN run
screen. The display is:

4A-B 5MFC 6mode ↓7flow 8presU 9tempU

See Sections 3.5.1 to 3.5.9 for detailed information on each SETUP function.

Note
Some screens (e.g., the SETUP menu) go beyond the two lines provided by thedisplay. This is indicated by a flashing arrow in the second line of the display.
Press the [←] and [→] keys to move the cursor to access the lines that are NOT
visible or directly enter the number of the hidden menu choice if you know it.

3.5.1<1molbloc> PURPOSE
To initialize a molbloc when it is connected to molbox1+ and/or to identify the molbloc(s)currently connected to molbox1+. To determine the gases with which a molbloc has beencalibrated.
 PRINCIPLE
molbox1+ uses molbloc specific calibration information contained in the molbloc's EEPROM
to determine whether it should operate in molbloc-L or molbloc-S mode and in its calculationof flow through the molbloc. For the molbox1+ to correctly calculate the flow through themolbloc, the molbox1+ must use information on the currently active molbloc. molbloc EEPROM
information is read and stored by molbox1+ in the molbox1+ power up sequence whenmolbox1+ is turned on by selecting [SETUP], <1molbloc>.
The <1molbloc> function should be used each time there is a change in the molbloc
connected to a channel to assure that molbox1+ uses the correct molbloc information on
subsequent measurements. The <1molbloc> function can also be used to display identifying
information on the molblocs currently connected to the molbox1+ channels and to determine
the gases with which the molbloc has been calibrated.
 OPERATION
To access the molbloc function press [SETUP],and <1molbloc>. The function activates forboth channels without additional prompts or entries.

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To view the gases with which the molbloc is calibrated, press [ENTER] in the molbloc
identification screen to view the molbloc’s gas list. After viewing, press [ESCAPE] to returnto the current run screen.

3.5.1.1

molbloc-L and molbloc-S Size and Range
Designations

Until mid-1999, molbloc-L elements (molbloc-S was not available at the time)
were always identified by “Range”. The molbloc-L “Range” is the molbloc’s
nominal full scale flow in Nitrogen (N2) at an operating pressure of 250 kPa.
Actual molbloc ranges change with the molbloc pressure dependent calibration
type and gas (see Section 1.2.5.1.2). Since mid-1999, in addition to nominal range,
molbloc-L elements have been designated by size with a sizing code (see Table 31).
On molbloc EEPROMs, the molbloc is still identified by its nominal range rather
than by its size. The identification of the molbloc displayed by [SETUP],<1molbloc> identifies molbloc-L by both its nominal range and sizing code.
molbloc-L size and range designation correspondence are given in Table 31.
Table 31. molbloc-L Size and Nominal Range Designations
molbloc“NOMINAL
RANGE”DESIGNATION

molbloc-L SIZEDESIGNATION

10 sccm

1E1

50 sccm

5E1

100 sccm

1E2

200 sccm

2E2

500 sccm

5E2

1 slm

1E3

5 slm

5E3

10 slm1E4

30 slm3E4

100 slm

1E5

molbloc-S elements are also identified by size designations, each of which relate to a
specific molbloc-S KF value. molbloc-S flow ranges depend on calibration type andthe pressure limitations of the application and molbox used. For information on thepossible molbloc-S flow ranges with various operating pressures, see Section
1.2.5.2.2). molbloc-S size and KF value correspondence are given in Table 32.
Table 32. molbloc-S Size and Pressure to Flow Conversion Ratio (KF)
KF
(sccm/kPa)© 2010 Fluke Calibration

molbloc-S SIZEDESIGNATION

10

1E1-S

20

2E1-S

50

5E1-S

100

1E2-S

200

2E2-S

500

5E2-S

1,000

1E3-S

2,000

2E3-S

5000

5E3-S

10000

1E4-S

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3.5.2<2stab> PURPOSE
To change the stability limit that serves as the criterion for the flow Ready/Not Ready
indication (see Section 3.1.3).
 PRINCIPLE
molbox1+ continuously monitors the rate of change of flow through the molbloc to which it isconnected and compares this rate to the stability limit to make a Ready/Not Readydetermination (see Section 3.1.3). The STABILITY function allows the stability limit to be
adjusted by the user to increase or decrease the stability required for a Ready (<*>) condition
to occur.

Note•

The default stability limit is + 0.1 sccm/second (or equivalent in anotherflow unit). The stability limit value is automatically converted when theflow unit of measure is changed.

•

The stability limit is separate and different from the RATE DISPLAY
function (see Section 3.4.6.1) which allows the current rate of change offlow to be displayed.

 OPERATION
To adjust the stability limit press [SETUP] and select <2stab>. The display is:1.

Entry field for setting the desired stability limit in the current flow unitof measure. Recalls the default stability limit or the last stability limit
set.

Flow stability test:
0.1 sccm/s

Edit the stability limit setting as desired. Pressing [ENTER] activates the stability limit for therange and returns to the current run screen.

Note•

The stability limit value is automatically converted when flow units ofmeasure are changed.

•

The [RES] setting affects the resolution of the stability limit value. If thestability limit display does not have enough resolution to set the desired
value, use [RES] to adjust the resolution (see Section 3.4.9).

3.5.3<3ADJ>

 PURPOSE
To apply adder (FA) and multiplier (FM) coefficients to the flow measured by the molbox1+.
PRINCIPLE
The ADJ function gives the user the capability to adjust mass flow readings made by themolbox1+. This is accomplished by setting an adder and a multiplier.
The adder (FA) and multiplier (FM) adjust the displayed value of the flow through the molbloc
as calculated by the molbox RFM following:corrected flow = (calculated flow * FM) + FA
If a K factor is active (see Section 3.4.1), the adder and multiplier are applied to thecalculated flow before the K factor is applied.

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Using the Flow ADJ Function with molbloc-L to Handle a Gas Mixture
The flow ADJ function can be used to adjust flow readings to measure a gas mixture if themolecular weight and relative content of each component gas is known. Note that thismethod does not take into account the true viscosity, compressibility or critical flow coefficient
factor of the gas mixture. The thermodynamic properties of only the highest concentration
gas are used. Therefore, the uncertainty in the measured flow is increased and the method
is best when the highest concentration gas is greater than 90% of the mixture.
To use this feature, set the molbox1+ [GAS] (see Section 3.4.2) to the highest concentration
gas, then adjust the flow multiplier by:molecular weight of the mix
molecular weight of the gas selected on the molbox

For example, to adjust a gas mix that is 95 % Nitrogen (N2) and 5 % Oxygen (O2): Calculate the molecular weight of the mix.
N2 molecular weight = 28.016
O2 molecular weight = 31.999
Mix molecular weight = (28.016 x 0.95) + (31.999 x 0.05) = 28.215
 Select N2, the highest concentration gas, as the molbox1+ gas.
 Calculate:molecular weight of the mix
molecular weight of the gas selecton on the molbox=

28.21528.016= 1.0071

 Set flow multiplier in ADJ function to 1.0071.
 OPERATION
To access the ADJ function press [SETUP] and select<3adj>. The display is:

Adder: 0
sccm
Mult: 1.00000

Edit the values as desired. Pressing [ENTER] returns you to the MAIN run screen with theedited adder and multiplier values applied.

 Caution•

The adder is expressed in current flow units and is NOT automaticallyconverted when flow units are changed. Adder values must be entered in
the current flow units. The multiplier is dimensionless.

•

The flow adder and multiplier of the ADJ function, if different from 0 and 1,
alter the flow readings made by the molbox1+. The ADJ function is always"ON" with no indication on the run screen of the current adder andmultiplier values and will be applied to the flow value of any attachedmolbloc. When using adders and multipliers, great caution should betaken to ensure that they are entered and changed correctly and that they
are 0 and 1 if no adder or multiplier effect is desired.

3.5.4<4A_B>

 PURPOSE
To turn ON and OFF special molbox1+ operating modes that use molbox1+ channels A andB together.
 PRINCIPLE
There are two A_B modes. In both of these modes molbox automatically switches between
the molblocs on its two channels and uses readings from both. The two A_B modes are:© 2010 Fluke Calibration

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3. OPERATION•

Additive mode (A+B) (see Section 3.5.4.2).

The additive mode sums the flow on channels A and B. It is designed for using two molblocs
in parallel to measure flows greater than the maximum flow range of a single molbloc.
•

Ratiometric mode (A/B) (see Section 3.5.4.3).

The ratiometric mode determines the ratio of the flow through two molblocs. This can provide
a convenient, system controlled, method for comparing molblocs to determine the coherence
between different ranges.

3.5.4.1

General Operation (Aspects Common to Both A_B
Modes)To access A_B modes, press [SETUP], <4A_B> and select the desired mode(<1A+B>, <2A/B>). Once the mode is selected, molbox1+ returns to the MAIN
run screen with the selected mode active. An indication of the active A_B mode
will be in the lower right of the MAIN run screen when space is available. To
cancel operation of an A_B mode, press the [A/B] function key (see Section
3.4.7) and operation returns to normal single channel mode.
When operating in an A_B mode, channel A is the dominant channel so thechannel specific functions applied (gas, flow unit, stability test, K factor, etc.)
will be those currently selected for channel A. Tare and leak check still apply toeach channel individually. Purge automatically purges channel A and thenchannel B (see Section 3.4.4).
When in an A_B mode, the channel indicator LED switches between channels
showing the channel that is currently active. The P&T function displays (seeSection 3.4.5) also switch as molbox1+ switches from channel to channel todisplay values for the currently active channel.
In an A_B mode, molbox1+ reads on one channel until either a Ready reading is
obtained or for up to 10 seconds, whichever comes first. If the last two single
channel readings were Ready, the A+B or A/B result is displayed as Ready. If
one or both of the last two single channel readings was Not Ready, the A+B or
A/B result is displayed as Not Ready (see Section 3.1.3).

Note•

It is helpful to set the molbox1+ stability setting as low as ispractical in any A_B mode to allow for flow stabilization oneach channel. To change the molbox stability setting, select[SETUP], <2stab> (see Section 3.5.2).

•

In A_B mode operation, molbox1+ may stay on one channel
up to 10 seconds waiting for a Ready reading. The first valid
reading after entering A_B mode may require 20 seconds
and subsequent readings up to 10 seconds.

•

It is not possible to operate A_B modes when the active BPR
mode is Auto due to internal valving conflicts. molbox1+ will
deny access to the A_B modes if the current BPR mode is
Auto and will not allow the user to select Auto mode whenan A_B mode is active (see Section 3.6.9).

•

A+B and A_B mode are supported only when molblocs ofthe same type are used. For example molbloc-S andmolbloc-S. The option is not available for a molboc-S andmolbloc-L combination

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3.5.4.2


A+B mode

PURPOSETo operate two molblocs simultaneously on molbox1+ channels A and B andobtain a flow rate which is the sum of the flow through the two molblocs.


PRINCIPLE

In A+B mode molbox1+ makes measurements on one channel and then theother channel. The flow rate displayed is the sum of the two most recent channel
readings, updated each time a channel reading is complete. This allows two
molblocs to be used together in parallel to measure flows greater than the range
of a single molbloc.


SET UPBest results with A+B mode are obtained when the two molblocs are mounted inparallel, symmetrically. A common regulator should be used with as little tubing,fittings, etc., as possible between the point where flow is split upstream of the two
molblocs and rejoined downstream. Standard hardware setups (molstics) for
A+B operation are available from Fluke Calibration.


OPERATION

To activate A+B mode, press [SETUP], select <4A_B> and then select <1A+B>.
molbox1+ returns to the MAIN run screen in A+B mode. The MAIN run screen in
A+B mode is:1.

Ready/Not Ready indication.

2.

Sum of channel A and channel B's two most recent
flow rate readings and the unit of flow.

3.

The gas that is being flowed.

4.

Rate of change of flow for the A+B results in units offlow per second.

5.

Indication that A+B mode is active (if space isavailable).

* 45.0775 slm N2
R 0.002/s A+B

The MFC run screens (if the molbox1+ has the optional MFC control feature) areunchanged except that the top line indications are A+B flow.

3.5.4.3


A/B Mode

PURPOSETo operate two molblocs simultaneously on molbox1+ channels A and B anddisplay the ratio of their flow rates.


PRINCIPLE

In A/B mode, molbox1+ makes measurements on one channel and then theother channel. The individual flow rate measured by each channel is displayed
as it is read and information on the ratio and disagreement between the twochannels is also calculated and displayed.
This function is intended to provide a convenient, system controlled, means ofcomparing two molblocs, for example to check the coherence of measurements
made by different molblocs.


SET UP

When using A/B mode to compare two molblocs, the two molblocs are connected
in series. The volume between the two should be minimized and the upstreampressure regulation should be as stable as possible to facilitate the establishmentof the steady state flow condition that must exist for a valid comparison to be made.
When selecting the hardware setup for running an A/B mode comparison, it is© 2010 Fluke Calibration

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3. OPERATION

important that the resulting setup allows each molbloc to operate under thecorrect pressure conditions for that molbloc’s calibration type. It is helpful to set
the molbox1+ stability setting as low as is practical in any A_B mode to allow forflow stabilization on each channel. To change the molbox1+ stability setting,select [SETUP], <2stab> (see Section 3.5.2).

Note
A/B operation is not recommended with 1E5 molblocs due totheir low differential pressure range.


OPERATION

To activate A/B mode, press [SETUP], select <4A_B> and then select <2A/B>.
molbox1+ returns to the MAIN run screen in A/B mode. The MAIN run screen in
A/B mode is:1.

Ready/not ready indication.

2.

Last flow measurement on currently active channel
with flow unit.

3.

The gas that is being flowed.

4.

The ratio of the two most recent channel readings(A/B).

5.

The difference in percent between the two mostrecent channel readings.

* 101.305 sccm N2
A/B 0.99803 D-01.97%

Though the optional MFC control functions are still active in A/B mode, the MFC
run screens are not available.

Note
To return to single channel mode, use the A/B function to selecteither A or B molbloc.

3.5.5<5MFC>

 PURPOSE
To create, store and edit the MFC profiles used by the optional MFC control function (see Section 3.4.8).

Note
The MFC control function is an optional feature of molbox1+. If this option
was not ordered with the molbox1+, the 1mfc function of the SETUP menu
will not be active.
 PRINCIPLE
MFC profiles are used by molbox1+ to configure the MFC function. MFC profiles define theanalog signal range of the MFC and the relationship between the analog signal range and theflow range of the MFC. This information allows molbox1+ to operate with the correct signal
for the current MFC and to convert the MFC analog signals to the corresponding flow or %FS values when desired.
MFC profiles are set up using [SETUP], <5MFC>. MFC profiles are stored by molbox1+
under profile numbers. This profile number is used to select the MFC profile when the MFC
function is activated using the MFC function key (see Section 3.4.8). Up to 26 MFC profiles
can be defined and stored.
MFC profiles are designed to allow the user to set up the profiles of the MFCs typicallycalibrated by or used with molbox1+ so that they can be conveniently recalled from a lookup
table when needed.

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MFC profiles #1 and #2 are factory profiles and cannot be edited. Profile #1 sets the MFC
control option to work in Volts with no flow range specified. Profile #2 sets the MFC control
option to work in milliamps with no flow range specified.
 OPERATION
To create or edit an MFC profile, press [SETUP], <5MFC>.
Enter profile number#4

The display is:
Select the profile number to edit and press [ENTER].

Note
MFC profiles #1 and #2 are factory default profiles for working with the MFC
function directly in analog units without specifying MFC flow range or units.
Profile #1 is 0 to 5 V, profile #2 is 4 to 20 mA (see Sections 3.4.8, 3.5.5).
Input type:1voltage2current

The display is:
Select the analog signal type of the MFC and press [ENTER].

The next display is used to enter the full scale voltage or current. Enter the full scale voltage
of current of the MFC and press [ENTER]. If the MFC signal selected was current (mA), youare also be prompted to enter the MFC 0 flow current output. molbox1+’s MFC control
function does not support mixed current/voltage MFCs.
The next selection specifies the flow units of measure forthis MFC profile. See Section 3.4.3 for an explanation of theunit selections.

Flow unit 1std 2user
3perfect

After the flow unit of measure has been selected the display
prompts for the range which will be entered in thepreviously selected units. Enter the numerical value of fullscale of the MFC in flow units.

Enter range
100.000 sccm

The next selection specifies whether the device is a mass
flow meter that measures flow only (MFM) or a mass flow
controller (MFC). Choose <1MFM> if the device for thisprofile measures only, choose <2MFC> if the device
measures and controls flow.

Device Type
1measure
2controlOnce the device type has been selected, editing is complete and a prompt to edit the next
profile # is presented. Pressing [ESCAPE] returns to the MFC function. Pressing [ESCAPE]
again returns to the current run screen.

Note
To clear/reset all MFC profiles, except #1 and #2 factory default profiles,
use [SPECIAL], <1reset>, <3mfc>.

3.5.6<6REG>

 PURPOSE
To turn the MFC control regulation mode ON and OFF, and to set the regulation period forregulation mode.

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3. OPERATIONNote
The REGE function affects the molbox1+ MFC control function. The MFC
control function is an optional feature. If this option is not installed in themolbox1+, the REG function of the SETUP menu is not active.
 PRINCIPLE
Regulation mode is designed to allow an MFC to be used with molbloc/molbox to precisely
set flows as measured by the molbloc/molbox. This feature allows an MFC to be used tocontrol flows to specific values as measured by the molbloc/molbox.
When the molbox1+ MFC function is active, set points can be sent to the MFC. In normal
operation, the set point entered is the set point signal sent to the MFC and that set point isheld constant until a new set point is given. The molbloc/molbox is used to read the flow
resulting from that MFC setpoint.
Regulation mode allows a set point to be given in terms of the desired flow through themolbloc as measured by the molbox1+. In regulation mode, the molbox1+ regularly readjusts
the actual set point applied to the MFC as needed to adjust flow to the desired flow value
through the molbloc. At each regulation cycle, the molbox1+ corrects the set point to the
MFC based on the difference between actual flow through the molbloc and the desired flow.
The regulation period sets the time interval between each regulation cycle.

Note
If there is a significant volume between the molbloc and the MFC,
regulation will be improved by increasing the regulation period.
 OPERATION
To activate or deactivate regulation mode and to set the regulation period, press [SETUP]
and select <6reg>.
Regulation Period(0 disables): 0

The display is:

If 0 (zero) is entered, regulation mode is inactive. If a value greater than 0 (zero) is entered,regulation mode is activated and the regulation period is value entered in seconds.
Maximum regulation period: 99 seconds
Minimum period: Single channel operation:
A+B Mode:

2 seconds
10 seconds

Typical effective regulation period: Single channel operation:
A+B Mode:

5 seconds
20 seconds

When the regulation mode is active, <R> is displayed in the bottom right hand corner of theMAIN run screen (when space is available).

3.5.7<7FLOWU>

 PURPOSE
To customize the selection of flow units of measure that are available for selection from the[UNIT] function key (see Section 3.4.3).
 PRINCIPLE/OPERATION
See Section 3.4.3.5.

3.5.8<8PRESU> PURPOSE
To select/change the unit of measure in which molbox1+ displays pressure values.
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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL OPERATIONTo set the unit of measure in which molbox1+ displays pressure values, press [SETUP] andselect <8presU>.
Pressure unit type:1SI 2other 3user

The display is:

Select the unit type desired, then select the unit desired. After the unit selection, operation
returns to the run screen with the selected pressure unit of measure active.
The pressure units of measure available are listed in Table 33.
Table 33. Pressure Units of Measure Available<1SI><2Other><3User>*<1Pa><1psi><1user><2kPa><2psf><3mPa><3inHg><4mbar><4inWa><5bar><5kcm2><6mmHg><7mmWa>*3User: User defined unit.

Note•

The “user” unit is defined in terms of user units/Pa when the user unit
is selected.

•

See Section 7.1.1 for definition of the pressure unit conversions usedby molbox1+.

3.5.9<9TEMPU> PURPOSE
To select the unit of measure in which molbox1+ displays temperature values.
 OPERATIONTo set the unit of measure in which molbox1+ displays temperature values, press [SETUP]
and select <9tempU>.
Temperature unit:
1celcius 2fahrenheit

The display is:

Select the desired unit. After the unit selection, operation returns to the run screen with theselected temperature unit active.

Note
See Section 7.1.2 for definition of the temperature unit conversions usedby molbox1+.

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3. OPERATION

3.6[SPECIAL] PURPOSE
The [SPECIAL] key accesses a menu of molbox1+ functions and settings that are less commonly or not
normally used in regular operation. These functions include:<1reset>Access and execute various reset options (see Section 3.6.1).

<2level>Set user protection levels that restrict access to certain functions and to edit the user
password (see Section 3.6.2).

<3ul>

Set upper pressure limit alarm (see Section 3.6.3).

<4cal>

View and adjust the molbox1+ pressure transducers, reference resistors and MFC analog
option (see Section 3.6.4).

<5prefs>

Set display screen saver time, unit ID number and date and time (see Section 3.6.5).

<6remote> View and edit molbox1+ COM port (RS232) and IEEE-488 interface settings (see Section 3.6.6).
<7drivers> Control the on/off of molbox1+’s optional 12 V drivers (see Section 3.6.7).
<8head>Set the height for the pressure fluid head correction (see Section 3.6.8).

<9BPR>

Set back pressure ratio (BPR) mode (molbloc-S operation only) (see Section 3.6.9).

 OPERATION
To access the SPECIAL menu, press [SPECIAL] from the MAIN run screen.
1reset 2level 3ul
4cal 5prefs 6remote ↓7drivers 8head 9BPR

The display is:

Select the desired function.
See Sections 3.6.1 to 3.6.9 for detailed SPECIAL function descriptions.

Note
Some screens (e.g., the SPECIAL menu) go beyond the two lines provided by thedisplay. This is indicated by a flashing down arrow in the second line of thedisplay. Press the [←] and [→] keys to move the cursor to access the lines that are
NOT visible or directly enter the number of the hidden menu choice if you know it.

3.6.1<1reset> PURPOSE
To reset various molbox1+ settings to default or factory values.
 PRINCIPLE
molbox1+ stores its user definable settings in non-volatile memory. The reset menu allows
the user to selectively or completely reset these settings to factory defaults. Reset clears
settings that the user may have made, and should be used only to restore the molbox1+ to a
known state. molbox1+ will go through its reboot routine after any type of reset is executed.

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To access the reset choices press [SPECIAL] and select<1reset>. The display is:

1sets 2units 3mfc
4cal 5all

Select the desired reset. After confirmation, the reset occurs. A reset always puts themolbox1+ through its start up routine as if power had been turned OFF and back ON.
See Sections 3.6.1.1 through 3.6.1.5 for detailed information on the specific reset choices.

Note
RESET functions change user settings that affect flow measurement. If
not used properly, resetting can cause out of tolerance measurements.
RESET functions should only be used by qualified personnel withreference to this manual for information on the RESET functions.

3.6.1.1<1sets>PURPOSE/OPERATION

To access Reset - Sets, press [SPECIAL] and select <1reset>, <1sets>.
Reset - Sets clears and sets to default the user settings for various measurements.
These include:•

Flow unit of measure to sccm (see Section 3.4.3).

•

Pressure unit of measure to kPa (see Section 3.5.8).

•

Temperature unit of measure to °C (see Section 3.5.9).

•

Gas type to N2 (see Section 3.4.2).

•

Stability criterion to 0.1 sccm (see Section 3.5.2).

•

K factor to 1 (see Section 3.4.1).

•

DISPLAY function to Rate (see Section 3.4.6.1).

•

RPT Tare value to 0 (see Section 3.4.4.1.1).

•

Tare to upstream pressure (see Section 3.4.4.1.1).

•

Flow adder to 0 and flow multiplier to 1 (see Section 3.5.3).

•

Resolution to 0.001 % (see Section 3.4.9).

•

BPR mode to Auto (see Section 3.6.9)

3.6.1.2
<2units>

PURPOSE/OPERATION

To access Reset - Units, press [SPECIAL] and select <1reset>, <2units>.
Reset - Units clears and sets to default all UNIT OF MEASURE functions. These include:© 2010 Fluke Calibration•

Six flow units of measure selectable from [UNIT] to defaults (see Section
3.4.3).

•

Flow unit of measure to sccm (see Section 3.4.3).

•

Reference temperature for uxxx units of measure to 0 °C (seeSection 3.4.3.3).

•

Volume flow unit of measure conditions to molbloc for temperature andstandard atmospheric pressure for pressure (see Section 3.4.3.4).

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Pressure unit of measure to kPa (see Section 3.5.8).

•

User pressure unit coefficient to 1.00/Pa (see Section 3.5.8).

•

Temperature unit of measure to °C (see Section 3.5.9).

3.6.1.3
<3MFC>PURPOSE/OPERATION

To access Reset - MFC, press [SPECIAL] and select <1reset>, <3MFC>.
Reset - MFC clears and sets to default all functions associated with the optional
analog MFC control. These include:•

Set MFC channel to 0 (inactive) (see Section 3.4.8).

•

Set regulation mode to OFF (see Section 3.5.6).

•

Set MFC profile to 1 (see Section 3.4.8.2).

•

Clear/delete user defined MFC profiles (see Section 3.5.5).

3.6.1.4<4cal>PURPOSE/OPERATION Caution
Use special caution with this reset as critical calibration data
may be altered.
To access Reset - Cal, press [SPECIAL] and select <1reset>, <4cal>.
Reset - Cal clears and sets to default the user calibration coefficients formolbox1+ Reference Pressure Transducers (RPTs) (see Section 5.2). This
includes:•Upstream and downstream absolute RPTs:
Adder
0
Multiplier:1
Calibration Date: 19980101

Note
Reset - Cal has NO effect on the reference resistance values
used to calibrate molbox1+s internal ohmic measurement
system (see Section 5.4) or on the calibration coefficients for the
optional MFC control function (see Section 3.4.8).

3.6.1.5<5all>PURPOSE/OPERATIONTo return molbox1+ to the original, as delivered factory condition. Performs theSETS, UNITS, CAL and MFC RESET functions and resets all other settablevalues to defaults. This includes communications port settings.
To access Reset - All, press [SPECIAL] and select <1reset>, <5all>.

 Caution
Use special caution with this reset as critical calibration data
may be altered.

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3.6.2<2level> PURPOSE
To set user protection levels that restrict access to certain functions and to edit the password
required for changing user levels.
 PRINCIPLE
molbox1+’s front panel user interface provides the means to access all molbox1+ user
def in e dda t a,s et t i ngs
andf u nc t i ons
i nc lu d in g
c a l ib r a t i on
d at a .
Inadvertent, uninformed or unauthorized altering or deleting of data, settings and functions
could require extensive reconfiguration by the user and might cause invalid readings. For
these reasons, depending upon the application in which molbox1+ is being used, it may bedesirable to restrict access to certain functions. The USER LEVEL function makes thispossible. Four different levels of security are available: none, low, medium and high.
Access to changing security levels can be left open, or be protected by a password so that
security levels can be used as a convenient way to avoid accidental changing of data or as asecured means of preventing tampering with molbox1+ settings.

3.6.2.1

Security Levels

The security levels are structured to support typical operating environments as follows:
None

This level is intended for use only by the system manager and/or
calibration facility. It allows access and editing in all areas including
critical metrological i nf o r m ati on a n d o th er s et t in gs t ha taf f ec t measurement integrity.

Low

Low security is designed to protect the specific metrologicalinformation and SYSTEM DIAGNOSTIC AND MAINTENANCE
functions of the system against accidental alteration. It is intended foran advanced operator performing many different tasks. Low security
is the default user level setting.

MediumMedium security is designed to protect specific metrologicalinformation in the system and to assure that the molbox1+ isoperated using consistent operational parameters.

High

High security protects all operating parameters. It is intended tominimize operator choices (e.g., to perform repeated identical tests
under consistent conditions).

 Caution© 2010 Fluke Calibration•

molbox1+ is delivered with the security level set to low to
avoid inadvertent altering of critical internal settings but withunrestricted access to changing security level setting. It is
recommended that the low security level be maintained at all
times and password protection be implemented if control
over setting of security levels is desired.

•If there is a risk of unauthorized changing of the security
level, changing authority should be password protected (seeOPERATION of this section).

•

The High security level disables remote communications
and returns an error message (“ERROR”) to all remotecommands. All other security levels have NO effect on
remote communications.

Page 98

3. OPERATIONThe security levels are structured to support typical levels of operation.
Specifically, the security levels prevent execution of the functions accessed by
the key strokes marked by “•” in Table 34.
Table 34. Security Levels - Functions NOT Executed Per Function/Level
KEYS

LOW

MEDIUM

HIGH

[K]

•

[GAS]

•

[UNIT]••[UNIT] (change temperature/pressure conditions)••[TARE] (access menu)[TARE], <1tare>, <select tare pressure>••[TARE], <2purge> change purge time••

[TARE], <4AutoZ>, <4run>

•

•

[P&T]

•

[DISPLAY]••[DISPLAY] (change times/target)

•
•

[A/B]
[MFC]

•

•

[RES]

•

•

[SETUP], (access to menu)•[SETUP], <1molbloc>•[SETUP], <2stab>

•

•

•

[SETUP], <4A_B>••[SETUP], <5MFC>••[SETUP], <6mode>••[SETUP], <7flowU>••[SETUP], <8presU>••[SETUP], <9tempU>••[SPECIAL], <1reset>••[SPECIAL], <1reset>, <1sets>••[SPECIAL], <1reset>, <2units>••[SETUP], <3adj>••[SPECIAL], <1reset>, <3MFC>

•

•

•

[SPECIAL], <1reset>, <4cal>

•

•

•

[SPECIAL], <1reset>, <5all>

•

•

•
•

[SPECIAL], <3UL>[SPECIAL], <3UL> (change setting)••[SPECIAL], <4cal>

•

•

•

•

[SPECIAL], <5prefs>••[SPECIAL], <5prefs>, <1ScrSvr>

•

•

•

•

[SPECIAL], <4cal>, <any 3edit>[SPECIAL], <5prefs>, <2ID>, <2edit>

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KEYS[SPECIAL], <5prefs>, <3time> (make changes)

LOW

MEDIUM

HIGH

•

•

•
•

[SPECIAL], <6remote>[SPECIAL], <6remote> (changes settings)••[SPECIAL], <7drivers>•••

Remote communications disabled

OPERATION

Notemolbox1+ is delivered with NO active password so access to
the User Level menu is open. The user level is set to <1Low>.
User levels can be changed freely until a password has beencreated. RESET functions (see Section 3.6.1) do not affect the
password setting.
To access the USER LEVEL function, press [SPECIAL], <2level>.
If NO password yet exists or if the correct
password has been entered, the display is:

1change user level3edit password

Selecting <1change user level> brings up the
restriction menu:

Restriction: 1none
2low 3medium 4highSelect the desired restriction level, or press [ESCAPE] to return to the current
run screen.
Selecting <2edit password> displays the user
password and allows it to be edited.
Passwords can be up to six numbers in lengthand cannot start with a zero.

Password: pppppp
0 disables password

If 0 is entered as the password value, then the password is made inactive and apassword will NOT be required to access the user level menu. This is the factory
default with a security level of <2low>.

 Caution
Once a password has been entered, the user level cannot bechanged without reentering the password.
If there is an active password, the molbox1+ password entry screen appears.
The user must enter the user defined password
or the factory secondary password to proceed.
When a password is entered correctly,
operation proceeds to the <1change user level2edit password> screen.

RFM SN
Password:

nnn-xxpppppp

The first field, <nnnn>, is the serial number of the molbox1+, followed by asecond field, <xx>, that counts the number of times that a secondary password
has been used. The second field increments each time a secondary password
is used. The third field, <pppppp>, is for normal password entry.
The factory secondary password is available in case the user password has
been misplaced or forgotten. A factory secondary password can be obtained bycontacting a Fluke Calibration Authorized Service Provider (see Section 7.4). The
factory secondary password is different for each molbox1+ and changes eachtime it is used.

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3.6.3

<3UL>

 PURPOSE
To set an upper pressure limit above which molbox1+ will produce a warning, interrupt
operation and isolate its internal pressure transducers.
 PRINCIPLE
molbox1+ contains two, high precision reference pressure transducers (RPTs). These canbe fatally damaged by large overpressures. The UL function uses molbox1+’s internal
capabilities to attempt to protect the RPTs against overpressure. molbox1+ continuously
monitors the pressure read by the RPTs. When the pressure passes the level set by the UL
function, molbox1+ warns the operator by sounding an audible alarm. Beyond the UL limit
there is an overpressure limit, which is not user selectable. If the pressure reaches theoverpressure limit, molbox1+ uses its internal valves to isolate the RPTs.
 OPERATION
To access the Upper Limit (UL) function, press [SPECIAL], <3ul>. The display is:
The indication is of the current upper limit setting in thecurrent pressure unit of measure. To specify a differentpressure unit of measure, use [SETUP], <8presU> (seeSection 3.5.8).

Transducer Max Pres:600.000 kPaa

To change the upper limit, enter the value desired (see max UL limits below) and press[ENTER]. The display returns to the MAIN run screen with the new upper limit in effect.
The maximum upper limit settings, which are also the default values, are 5 % above themolbox1+ maximum operating pressure ranges. For the molbox1+ models, the max UL
values are specifically:
For molbox1+ A350K:

315 kPa absolute (45 psia)

For molbox1+ A700K:

630 kPa absolute (91 psia)

For molbox1+S A1.4K: 1470 kPa absolute (213 psia)
For molbox1+S A2M:

2100 kPa absolute (304 psia)

The molbox1+ overpressure limits, which cannot be edited, are:
For molbox1+ A350K:

330 kPa absolute (48 psia)

For molbox1+ A700K:

660 kPa absolute (96 psia)

For molbox1+S A1.4K: 1540 kPa absolute (223 psia)
For molbox1+S A2M:

2200 kPa absolute (319 psia)

If the overpressure limit is exceeded, all molbox1+ internal valves close and normal operation
is interrupted. Normal operation can be reestablished by turning molbox1+’s power OFF andback ON or pressing [ENTER]. Be sure to correct the situation that led to the overpressure
condition prior to rebooting molbox1+ or pressing [ENTER]. See Sections 3.6.3.1, 3.1.4 foradditional details.

Note
UL is molbloc channel specific. There are separate UL settings formolbloc channel A and channel B operation.

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3.6.3.1

Upper Limit Alarm and Sequence

When the pressure reaches the upper limit, molbox1+ continues normal
operation but sounds an audible alarm. The alarm ceases if the pressure isdecreased below the upper limit.
When pressure reaches the overpressure limit,
all molbox1+ internal valves close, normal
operation ceases and the display indicates:

610.250 kPa 601.780
OVERP! CHK & PWR DWN

The top line indicates the current pressure measurement of the upstream (left)and downstream (right) RPTs. The bottom line is the over pressure warning.
Pressure indications that are grossly out of scale generally indicate that the
RPT(s) have been fatally over pressured.
Other menus can be observed but the MAIN run screen can not be accessed andno molbox1+ internal valves can be operated. To return the molbox1+ to normal
operation, it must be turned OFF and back ON or press [ENTER] from theoverpressure screen. When molbox1+ normal operation is reestablished, its
isolation valves will open. Be sure the situation that led to the overpressure
condition is corrected before attempting to reestablish normal operation.

Note

3.6.4

•

The upper limit and overpressure functions are intended touse molbox1+’s features to the extent possible to protect themolbox1+ reference pressure transducer (RPTs) against
overpressure.
The system is not failsafe and an
overpressure causing fatal damage to the RPTs canstill occur.
Ultimately, protection of the RPTs is the
responsibility of the user. RPTs damaged by overpressure
are not covered under the product warranty.

•

molbox1+ continuously monitors for maximum pressure.
Whenever the overpressure limit is exceeded, the pressure
value reached, time and date are logged to a
privileged location. This information can be of use indetermining the events that led to an overpressure situation.

<4cal>

To calibrate and adjust the molbox1+ reference pressure transducers, ohmic measurement
system, optional MFC control function and the calibrated molbloc flow.
The CALIBRATION functions are considered part of molbox1+ maintenance and are
therefore covered in the maintenance section of this manual (see Section 1).

3.6.5<5Prefs>

 PURPOSE
To access a menu of molbox1+ internal operational preferences and functions.
These include:<1ScrSvr> View and change the SCREEN SAVER function (see Section 3.6.5.1).
<2ID>

View and edit the molbox1+ user ID (see Section 3.6.5.2).

<3time>View and edit the internal time and date settings (see Section 3.6.5.3).

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 OPERATION
To access the PREFS menu press [SPECIAL], and select<5prefs>. The display is:

1ScrSvr 2ID 3time

Select the desired function.
See Sections 3.6.5.1 to 3.6.5.3 for detailed information on each PREFS function.

3.6.5.1<1ScrSVR>

PRINCIPAL

To adjust the time setting of molbox1+’s SCREEN SAVER function.


PRINCIPAL

molbox1+ has a SCREEN SAVER function which causes the display to dim after
a front panel key is NOT pressed for a certain amount of time. The default
screen saver time activates the screen saver after 10 minutes. The screen saver
activation time can be adjusted by the user or screen saving can be completely
eliminated.


OPERATION

To access the SCREEN SAVER function, press [SPECIAL] and select<5prefs>, <1ScrSav>. Edit the time, in minutes, after which the screen saver will
activate to dim the screen. Set zero to eliminate the SCREEN SAVER function.

Note
Setting screen saver time to zero eliminates the SCREEN
SAVER function so that the display permanently remains at fullbrightness.

3.6.5.2<3ID>

PURPOSETo view or edit the molbox1+ user ID and to view the molbox1+ serial number.


PRINCIPAL

molbox1+ has a factory programmed serial number that is included on the
product back panel and can be viewed in the introductory screen.
molbox1+ also allows the user to store a unique, twelve character, alpha numeric
ID number. This feature is frequently used to assign an organizational control ID(e.g., an asset number, tool number, standard number, etc.). The ID function
allows the ID number to be viewed and edited. It also displays the molbox1+
factory serial number.


OPERATION

To access the ID function press [SPECIAL] and select <5prefs>, <2ID>.
Select <1view> to view the current ID.
Select <2edit> to edit the ID.
The ID has twelve characters. When the edit screen is opened, the cursor is on
the first character. Numerical values can be entered directly from the keypad.
In addition, the [←] and [→] keys can be used to toggle through a list of available
alpha numeric characters. Holding the key slews through the characters.
Character order going up ([→]) is: blank space, symbols, lower case letters,
upper case letters, numbers. After selecting a character, press [ENTER] to
activate it and move to the next character field.

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When a character is selected the cursor moves to the next character. To leave a
blank character, press [ENTER] with the field for that character blank. Use thisfor the trailing characters if the ID being entered is less than twelve characters.
After the last of the twelve characters has been entered, the <Save ID?> option is offered.
Select <1no> to return to the ID edit screen. Select <2yes> to save the edited ID.

Note
The ID can be set remotely from a computer which is quite a bit
more convenient than entering characters from the keyboard(see Section 4.3.4.2, ID command). The ID cannot be cleared or
reset by any RESET functions (see Section 3.6.1).

3.6.5.3
<3Time>PURPOSETo view and edit the molbox1+ internal time and date settings.


OPERATION

To access the TIME function press [SPECIAL]
and select <5prefs>, <3time>. The display is:

Edit: 1time 2date
08:32:11 am 19980101

Select <1time> to edit the time. Edit hours, then minutes, then am/pm bypressing [ENTER] at each entry. Seconds go to zero when minutes are entered.
This can be used to synchronize the time with a time standard.
Select <2date> to edit the date.
YYYYMMDD format.

The date must be specified in

Note
The molbox1+ date and time are set to United States MountainStandard Time in the final test and inspection process at thefactory. If desired, use the TIME and DATE functions to set yourlocal time and date.

3.6.6<6REMOTE> PURPOSE
To configure the molbox1+ COM1, COM2 and IEEE-488 communication ports.
COM1 and COM2 communications.

To test PRINCIPLE
The molbox1+ has two RS232 communications ports referred to as COM1 and COM2 and asingle IEEE-488 port. COM1 and the IEEE-488 port are for communicating with a hostcomputer (see Section 4.1). COM2 is reserved for pass through communications with an
external device, (e.g., a multimeter, second molbox, MFC controller, etc.). These ports canbe set up from the molbox1+ front panel.
molbox1+ provides a self-test for its RS232 communication ports. The self-test allows
verification that the molbox1+ RS232 ports (COM1 and COM2) are operating properly andthat a valid interface cable is being used.
 OPERATION
To access the communication port configurations, press [SPECIAL] and select <6remote>.
Select <1COM1>, <2COM2>, or <3IEEE-488> to view and/or edit that port’s settings.
To access the RS232 self-test press [SPECIAL] and select <6remote>, <4RS232test>.

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3.6.6.1

COM1 and COM2

The COMx port settings can be adjusted. The settings are baud rate, parity, databits and stop bits. The available options are listed in Table 35.
Table 35. COM1 and COM2 Available Settings
BAUD RATE

300, 600, 1 200, 2 400, 4 800, 9 600, 19 200

PARITY

NONE, ODD or EVENDATA BITS

7 or 8STOP BITS

1 or 2The default COMx settings are 2400, E, 7,1 for both COM ports.
The molbox1+ appends a carriage return (<CR>) and a line feed (<LF>) to allmessages that are sent out of the COM1 port to the host. It looks for a carriage
return to terminate incoming messages and ignores line feeds. The user MUST
wait for a reply to each message sent to the molbox1+ before sending anothermessage to it (see Section 4.2.1).

3.6.6.2

IEEE-488

The IEEE-488 port address can be defined from 1 to 31. The default address is 10.
The molbox1+ sends a line feed (<LF>) and asserts the EOI line at the end of alltransmitted messages. It looks for a line feed and/or assertion of the EOI line toterminate incoming messages (see Section 4.2.2).

3.6.6.3

RS232 Self-Test

The RS232 self-test is provided to check the molbox1+ COM ports and theinterface cable independently of an external device or computer.
If you are having difficulty communicating with molbox1+ from a hostcomputer using RS232, the RS232 self test can help establish that themolbox1+ COM1 port you are trying to communicate with and the interface cable
you are using are good.
To run a self test of the RS232 ports (COM1 and COM2), press [SPECIAL] andselect <6remote>, <4RS232test>.
The display prompts you to connect COM1 to COM2 using a standard pin to pin
DB-9F to DB-9M RS232 cable (see Section 4.2.1.1).
Once the cable has been installed, press [ENTER] to run the self-test. The test
is first executed in the COM1→COM2 direction and then in the
COM2→COM1 direction.
If the COM1→COM2 test passes:
proceeds to COM2→COM1.

<PASSED> displays briefly and the test

If COM2→COM1 passes: <PASSED> is displayed briefly followed by theconclusion, <molbox1+ RS232 test has PASSED>.
If a test fails: Execution is suspended until [ENTER] is pressed.

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The molbox1+ RS232 test can fail for three reasons:
1. The RS232 cable being used is incorrect (see Section
4.2.1.1 for information on the correct cable).
2. COM1 and COM2 do NOT have the same serial
communications settings and therefore cannot
communicate together (see Section 3.6.6.1 to set the
COM ports).
3. COM1 or COM2 is defective.
The reason for failed communications is almost always a cableor incorrect RS232 interface settings. Be sure that these arecorrect before concluding that a COM port is defective.

3.6.7<7Drivers>

 PURPOSE
To control the output signals of molbox1+’s 8 channel, 12 V external drivers.

Note
The <3drivers> function is an optional feature of molbox1+. If this option
was not ordered with the molbox1+, the driver hardware has not been
installed and the operation of <3drivers> will have no effect.
 PRINCIPLE
molbox1+ external drivers are available to drive peripheral equipment in a molbox1+ system(e.g., manifolding valves for selecting gas supply to the molbloc or automatically directing
flow to molbloc channel A or B). The driver electrical connections are available from a rear
panel connector (see Section 7.2 for driver specifications and pin outs).
 OPERATION
To access the driver control function, press [SPECIAL] and select <7drivers>.
External Drivers: 1
2 3 4 5 6 7 8The display is:

Pressing the keypad numerical key driver number turns that driver ON and OFF with either amomentary or a toggled response. An active driver is indicated by <*> immediately following
the driver number. Pressing [ENTER] while in the External Drivers menu causes a menu toappear that allows selection of whether the driver actuation by selecting the driver number
will be <1momentary> or <2toggle>.

3.6.8<8Head> PURPOSE
To cause a pressure fluid head correction to be added or subtracted to the pressure
measured by the molbox1+ reference pressure transducers in order to predict the pressure atheight the height of the molbloc when the molbloc is at a level other than the molbox1+’sreference level.
 PRINCIPLE
molbox1+ measures absolute and differential pressure in molbloc flow elements. The
molbox1+ reference pressure transducers (RPTs) are calibrated with the height of the rear
panel pressure quick connectors as the pressure reference level. Sometimes, when
performing a calibration or test, the molbloc is at a different height than the molbox1+’spressure reference level. This difference in height, frequently called head, can cause a© 2010 Fluke Calibration

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significant difference between the pressure measured by the molbox1+ at its reference level
and the pressure actually present at the molbloc at a different height. In this case, it is useful
to make a head correction to the pressure measured by the molbox1+ in order to predict thepressure actually applied at a different height.
molbox1+ can calculate head pressures for all the gases it supports (see Section 3.4.2),
over its working pressure range. The HEAD function allows the difference in height between
the molbox1+ and the molbloc to be specified and causes the resulting head pressure to be
added to the pressure measured at the molbox1+ rear panel quick connectors.
[SPECIAL], <8head>, is used to specify the height difference between the molbox1+ rear
panel quick connectors and another height. Entering a height of zero turns the function off.

Note
Use of the HEAD function to assure in tolerance measurements is mostimportant when using molbloc-S at high pressures. Specifying the headheight within ± 3 in. (7.5 cm) is adequate to assure that, even in the worst
case, the uncertainty on the head correction will be insignificant relative tothe tolerance of the measurement.
 OPERATION
To access the HEAD function, press the [SPECIAL], <8head>. The display is:1.

Entry field for head height.

2.

Current molbox1+ gas selection.

Edit head height:
+ 25
cm
N2

Edit the head height to the desired value. Press [ENT] to return to the run screen with the
new head correction active. Press [ESC] to return with no changes.
Note
The reference height of the molbox1+
pressure measurement is the middle of themolbox1+ rear panel pressure quickconnectors. The head height should beentered as a positive value if the molbloc ishigher than the molbox1+ and negative if it
is lower.

Note•

The HEAD function is NOT channel specific. The HEAD height setting and
ON or OFF status remains the same as molbloc channels are changed.

•

When a head correction is being applied, it is indicated by <h> to the rightof the pressure unit in the [P&T] screen (see Section 3.4.5). When the headcorrection is zero, the <h> is not shown.

•

The head function is automatically disabled when running AutoZ (seeSection 3.4.4.4.2) and in the calibration run screen (see Section 5.2.4.1).

3.6.9<9BPR>

 PURPOSE
In molbloc-S operation, to select the molbox1+ BPR (back pressure ratio) measurement mode. The
molbox1+S BPR measurement mode is always on; there is no option to turn it off or use theauto selection option described below.
 PRINCIPLE
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When molbloc-S elements are used with molbox1+ the RPT which is normally used to readmolbloc downstream pressure, may be pneumatically connected to either the molbloc-S
nozzle’s upstream or downstream pressure, by molbox1+ internal valving. The two RPTs areused simultaneously upstream when possible to minimize the uncertainty on molbloc-S
upstream pressure measurement by averaging the two RPT readings. The upstream absolutepressure is the most critical measurement for calculation of the flow through molbloc-S.
Measurement of molbloc-S downstream pressure is only necessary to monitor the BPR(molbloc back pressure ratio). The value of BPR indicates whether the flow through themolbloc-S has achieved the necessary critical flow condition (see Section 3.1.5).
When the molbox1+ internal valves are positioned to connect one RPT upstream and theother downstream of the nozzle to determine BPR, the valve state is referred to as BPR ON(see Figure 11).

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Open
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: Closed

Figure 12. molbox1+ Internal Pneumatic Schematic –molbloc-S OPERATION, CHANNEL A, BPR ON

When the molbox1+ internal valves are positioned to allow both RPTs to measure themolbloc-S upstream pressure, the valve state is referred to as BPR OFF (see Figure 12).

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Closed
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 13. molbox1+ Internal Pneumatic Schematic –molbloc-S OPERATION, CHANNEL A, BPR OFF

Ideally, the user is able to monitor the BPR with BPR ON while setting flows and pressures,and once the flow is established, uncertainties can be minimized by turning BPR OFF gaining
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ON and BPR OFF, molbox1+ has a BPR mode called Auto that uses on-board logic todetermine when to turn BPR ON and OFF. In BPR Auto mode, the molbox uses cues basedon flow and pressure changes, stability, and proximity to the Reynolds number-based BPR
limits to determine when to switch between the BPR ON and BPR OFF valve states (seeSection 3.6.9). Auto is the default BPR mode and is considered the normal mode for manual
molbloc-S/molbox1+ use.
For users who prefer to avoid automatic valving, there are two other BPR modes. BPR OFF
mode keeps the molbox in the BPR OFF valve state at all times. BPR ON keeps the molbox
in the BPR ON valve state at all times. BPR OFF mode should be used with caution, as itprovides no monitoring of BPR to ensure that molbloc-S measurements are valid.

Note
When molbox1+ is used in BPR OFF mode, molbox cannot measure themolbloc-S downstream pressure and provides no monitoring or indicationof the BPR. molbox1+ cannot warn the user when the flow throughmolbloc-S is not critical and flow measurements are not valid. For
example, when the molbloc is at rest in BPR OFF mode, and atmosphericpressure is applied to both the upstream and downstream side ofmolbloc-S, the molbox1+ will indicate a false flow rate approximately equal
to the molbloc-S KF value times the value of atmospheric pressure in kPa.
If BPR OFF mode is used, the user must make sure that a sufficiently low
BPR is maintained while making molbloc-S flow measurements (seeSection 3.1.5). The [TARE], <5BPR> function can be used for quick BPR
checks (see Section 3.4.4.5).
 OPERATION
To access the BPR mode menu, press [SPECIAL], <9BPR>.
BPR mode:
1BPRoff 2BPRon 3Auto

The display is:

On a molbox1+S, BPR is always on. The menu does not provide a selection.
BPR mode:
BPR ONThe display is:

Making a BPR mode selection, actives the selected BPR mode and returns to the previous
RUN screen. [ESCAPE] returns to the previous RUN screen without changing the BPR mode.
Selecting <1BPRoff> causes, the molbox1+ internal valves to immediately switch to the BPR
OFF valve state (see Figure 12), and remain there until the user changes the BPR mode or
activates a function which causes a valve change (such as the [TARE], <5BPR> function, see
Section 3.4.4.5). In BPR OFF mode, the flow is calculated from the average of the two RPTpressure readings and the RPT pressures displayed in the P&T pressure screen are adjusted
using the dynamic tare feature, so both pressures are displayed equal to the average value(see Section 3.1.2 and 3.4.5)
Selecting <2BPRon> causes, the molbox1+ internal valves to immediately switch to the BPR
ON valve state (see Figure 11), and remain there until the user changes the BPR mode or
activates a function which causes a valve change. In BPR ON mode, flow is calculated fromthe upstream RPT measurement only. In BPR ON mode, there is no tare applied to the RPT
readings at any time.
Selecting <3Auto> does not necessarily immediately change the BPR mode.. Depending on
the current BPR mode, BPR mode changes occur as follows:
In Auto mode, in the BPR ON valve state:molbox1+ monitors the BPR value directly. If the BPR is safely below the BPR limit(calculated from empirical testing of molbloc-S choking ratios, see Section 3.1.5), then, once
the flow is stable within 0.5 % of reading for 3 seconds, molbox1+ switches to BPR OFF
valve state and begins live averaging of the RPT pressure values.
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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

In Auto mode, in the BPR OFF valve state:molbox1+ cannot monitor BPR, but based on the proximity of the most recently measured
BPR to the calculated BPR limit, if the current flow value changes enough that it is likely thatthe BPR is approaching the limit, molbox1+ switches to BPR ON valve state to check BPR
directly. It is highly unlikely that valve switching will occur during critical flow measurements
because, typically, high precision flow measurements are not made when flow is changing.
In Auto mode, when the valves are in BPR OFF state, flow is calculated from the average ofthe two RPT pressure readings as in BPR OFF mode. When the molbox1+ valves switch to
the BPR ON valve state in Auto mode, the tare can no longer be dynamically calculated
because the two RPTs are not measuring the same pressure. The most recent tare that was
automatically calculated during the BPR OFF valve state is used to correct the pressuresused and displayed in Auto mode until the valves return to the BPR OFF state again. This assuresthat flow measurements remain as consistent as possible during Auto mode valve switching
and that the tare value that is most likely to be correct is used at all times.

Note•

It is possible to change the BPR mode by remote communication withmolbox1+ and also to disable molbox1+ valve control and switching whilein any BPR mode (see Section 4.3.4.2).

•

It is not possible to operate A_B modes when the active BPR mode is Autodue to internal valving conflicts. molbox1+ denies access to the A_B
modes if the current BPR mode is Auto and does not allow the user toselect Auto mode when an A_B mode is active (see Section 3.5.4).

© 2010 Fluke Calibration

Page 110

4.

Remote Operation

4.1

Overview

Most of the molbox1+’s front panel functions can also be executed by commands from aremote computer. The host computer can communicate with the molbox1+ using the molbox1+ COM1
RS232 port or the IEEE-488 port. The command syntax is the same for either port except when using theIEEE STD. 488.2 Common commands.

4.2

Interfacing

Sending any command to the molbox1+ places it into a “soft” remote mode. The remote indicator in thelower right hand corner of the molbox1+ front panel is illuminated when molbox1+ is in this remote mode.
The indictor also flickers when remote communication is occurring. The menus usually accessed fromthe front panel are locked-out while in remote mode. Pressing the [ESCAPE] key returns the molbox1+
to local operation unless the “REMOTE” command was sent to the unit. The “REMOTE” command locks
out keypad operation until the “LOCAL” command is sent. In either level of remote mode the [P&T] key
still responds to allow the user to change the data being viewed on the molbox1+ main run display.
Most remote commands will return a reply within,500 ms. You must wait for this reply before issuing
another command to the molbox1+. This ensures that the molbox1+ has completed the command.
An exception to this is the use of any of the IEEE STD. 488.2 Common Commands (see Section 4.3.4.1)
via the IEEE-488 interface (common commands all start with an asterisk, “*”). The common commands
only generate a reply if using the COM1 port or if the query form of the common command is used(command followed by a “?”).
The following commands take more than,500 ms to reply:
ALLR, DP, FR, PR, RATE, SR, TAREGASTARESET, DEVICE=EXT, RESET

Up to 2 seconds to allow a new measurement.
Up to 5 seconds to complete a change.
Up to 10 seconds to complete.

Note
LabVIEW drivers are available for the molbox1+. These drivers allow users of the
National Instruments’ LabVIEW environment to create systems that include one ormore molbox1s using LabVIEW virtual instruments instead of using the remotecommands directly. The molbox1+ LabVIEW drivers are an abstraction of theremote commands into a consistent set of common and specificinstrument functions. The drivers can be obtained at NO charge from the DHI
worldwide web site, www.dhinstruments.com.

4.2.1

RS232 Interface

To establish RS232 communications a standard pin to pin DB-9F to DB-9M RS232 cablemust be used to connect the host COM port to molbox1+ COM1. The interface settings ofboth ports must be the same.

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Notemolbox1+ supports an independent RS232 self-test to verify that themolbox1+ RS232 ports are operating correctly and the interface cablebeing used is valid. Use this self-test to troubleshoot if you are having
difficulty
establishingcommunications
withmolbox1+
COM1(see Section 3.3.6.3).

4.2.1.1

COM1

The molbox1+ COM1 RS232 interface is located on the rear panel. It is a 9-pin male
DB-9F connector configured as a DCE device. Data is transmitted out of molbox1+
using pin 2, and is received on pin 3. This allows a standard pin to pin DB-9M to
DB-F RS232 cable to be used to connect to a DTE host. Handshaking is NOT
required or supported.
COM1 RS232 commands must be terminated with at least a single carriage return
character, while line feed characters are ignored. All RS232 responses from themolbox1+ are terminated with a carriage return character and a line feedcharacter.
Table 36. COM1 DB-9F Pin DesignationPIN #FUNCTIONDESCRIPTION

2
3
5

TxD
RxD
Grn

This pin transmits serial data from the molbox1+ to the host.
This pin accepts serial data from the host computer.
This pin is the common return for the TxD and RxD signals.

IBM PC/XT DB-9F
CONNECTIONS

4.2.1.2

IBM PC/XT DB-9M TO PPC3 DB9F
CONNECTION

DB-25M

DB-9F

DB-9M

DB-9F

2
3
7

3
2
5

3
2
5

3
2
5

COM2

The molbox1+ COM2 RS232 interface is located on the rear panel. It is a 9-pin female
DB-9M connector configured as a DTE device. Data is transmitted out of themolbox1+ using pin 3 and is received on pin 2. This allows a standard pin to pin
DB-9F to DB-9M RS232 cable to be used to connect to a DCE slave.
Handshaking is NOT required or supported.
COM2 can be used to allow the host computer to communicate with anotherdevice (e.g., another molbox or multimeter) through the molbox1+. This allows
the user to use one host COM port or IEEE-488 port to communicate with themolbox1+ and an additional RS232 device. Refer to the “#” remote command for
details (see Section 4.3.4.2, # Command).
Table 37. COM2 DB-9M Pin Designation© 2010 Fluke CalibrationPIN #FUNCTIONDESCRIPTION

2

RxD

3

TxD

4
5

DTR
Grn

This pin accepts serial data from another molbox1+ oranother device.
This pin transmits serial data from the molbox1+ to anothermolbox1+ or another device.
Data Terminal Ready. Held at + 5 Volts.
This pin is the common return for the TxD and RxD signals.

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4. REMOTE OPERATIONIBM PC/XT DB-25F TO DB-9M
CONNECTIONS

4.2.2

IBM PC/XT DB-9F TO molbox1++
DB9M
CONNECTION

DB-25F

DB-9M

DB-9F

DB-9M

2
3
7

3
2
5

3
2
5

3
2
5

IEEE-488 (GPIB)

The molbox1+ IEEE-488 interface is located on the rear panel. The physical and electricalinterface conforms to IEEE Std 488.1-1987 Subset E2 and IEEE Std. 488.2-1992. You should
NOT attempt to communicate with the IEEE-488 interface while using the COM1 interface.
The IEEE-488 receive buffer is 250 bytes deep. The molbox1+ will hold OFF release of the
NRFD handshake line until it can service and empty the receive buffer. This keeps the bufferfrom overflowing.
IEEE-488 commands must be terminated with a single line feed character along with theassertion of the EOI line. All IEEE-488 responses from the molbox1+ are terminated with a line
feed character along with the assertion of the EOI line. Replies are held in a buffer until thehost computer gets them, so it is possible to have old replies in this buffer, while you are
expecting new replies from a just issued command.

4.3

Commands
4.3.1

Command Syntax

All molbox1+ commands are ASCII strings. The user must wait for the molbox1+ to reply before
sending another command. An exception to this is the use of any of the IEEE STD. 488.2
Common Commands via the IEEE-488 interface (these Common Commands are shown first,
and always start with an asterisk, “*”). The common commands only generate a reply if using
the COM1 port or the query form of the common command is used (command followed by a “?”).

4.3.2

Command Summary
Table 38. Command Summary
SYNTAXPURPOSE*CLS*ESE(?)*ESR?
*IDN?
*OPC(?)*OPT?
*RST*SRE(?)
*STB?
*TST?
#
AUTOZERO(=)
ABORT
AIRW
ALLR

Clears the status registers and all queues.
Read or set the Event Status Enable register.
Read the Event Status Register.
Identify the product and software version.
Read or set the Operation Complete register (not applicable to the molbox1).
Read the molbox1+ options installed.
Reset user settings to factory defaults.
Read or set the Service Request Register.
Read the Status Byte.
Read the system self-test results.
Send a command string out of the molbox1+ COM2 port.
Read or set the status of the reference pressure transducers (RPTs) “AutoZ” function
Stop an active averaging, tare, leak check or purge cycle.
Read or set the humidity ratio of the gas, AIR
Read the next measurement of molbloc flow, the molbox1+ up and downstream
RPT pressure values, and molbloc temperature.
To actuate the internal buzzer for half of a second.
Read or set the back pressure ratio mode when using a sonic nozzle
Read the MFC measurement current if in ‘mA’ mode.
Read or set the configuration of the COM1 or COM2 port.
Read or set the current for an external MFC if in “mA’’ mode.
Read or set the internal clock’s date.

BEEPERBPR(=)
CIN
COMn(=)
COUT(=)DATE(=)

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALSYNTAXDEVICE=
DP
DRV
ERR
FA=
FCOEF
FR
FRA
FUNIT(=)
GAS(=)GASCAL(=)
GASCALS
ID (=)KFACT(=)
LEAKCK(=)
LOCAL
MEM
MFCCH(=)
MOLBLOCOHMS
PCAL
PCALDATE(=)
PCOEF
PR
PRHI
PRLO
PUNIT(=)
PURGE(=)
RANGE
RATE
RE
RES(=)READYCK(=)
REMOTE
RESET
SN
SR
SS(=)
STDRES(=)
TARE
TARESETUP(=)
TARESET(=)
TCAL (=)
TEMP
TIME(=)TOTAL(=)
TUNIT(=)
UDU(=)UL(=)
USERCAL(=)
UTEMP(=)
VALVE
VER
VLM(=)
VIN
VOUT(=)VSENSEVSUPPLYVVALTESTZOFFSET:HIZOFFSET:LO© 2010 Fluke Calibration

PURPOSE
Loads information on molbloc connected to molbox1+ into molbox1.
Read the differential pressure value being used to calculate flow.
Read or set the status of an external solenoid valve.
Read the last error message.
Start a single flow averaging cycle.
Read the coefficient to convert kg/s to the current flow units.
Read the next flow measurement.
Read the results of a completed flow averaging cycle.
Read or set the flow display unit.
Read or set the gas type being used.
Read or set the active molbloc calibration to use.
List all calibrations available in the active molbloc.
Read or set the molbox1+ ID.
Read or set the “K” factor.
Start a molbox1+ or system leak check cycle or check if a cycle is complete.
Enable the front panel controls if in remote and go to local.
Read the memory test status.
Read or set the MFC channel and output mode (voltage or current).
Read the active molbloc header data. Does not load molbloc information.
Read the most recent measurement of the active molbloc’s two PRTs.
Read or set the user RPT calibrations.
Read or set the user RPT calibration dates.
Read the coefficient to convert Pascal to the current pressure units.
Read the next molbloc average pressure.
Read the last measured upstream pressure (tare corrected).
Read the last measured downstream pressure (tare corrected).
Read or set the pressure display unit.
Read the progress of or start the purge cycle.
Read the range of the active molbloc.
Read the next available rate of change of flow.
Read the current Reynolds number.
Read or set the local flow display resolution.
Read or set a flag that is cleared by a Not Ready condition.
Enable remote local lockout operation.
Reset the molbox1+ settings to the default operating parameters.
Read the serial number of the molbox1+.
Read the next available ready status.
Read or set the stability required for a Ready <*> condition.
Read or set the PRT measurement system auto-calibration reference resistor
values.
Read the current tare conditions and the current tare.
Prepares the unit to tare.
Tare the upstream and downstream RPTs or set tare to a given value.
Read or set the molbloc temperature calibration (channel dependent).
Read the current molbloc temperature in the current units.
Read or set the internal clock’s time.
Read the progress of or start a new totalize cycle.
Read or set the molbloc temperature unit.
Read or set the user definable pressure unit.
Read or set the upper limit for the internal RPTs.
Read or set the user flow measurement adjustment.
Read or set the temperature reference used for the user flow units.
This command is obsolete and should not be used in new designs.
Read the molbox1+ version.
Read or set the volume units pressure & temperature conditions.
Read the MFC measurement voltage if in voltage mode.
Read or set the voltage sent to an external MFC if in voltage mode.
Read the voltage sensed at the MFC terminal.
Read MFC supply voltage.
Read voltage sensed at MFC valve test terminal.
Read or set the AutoZ pressure offset, (Poffset), for the high RPT .
Read or set the AutoZ pressure offset, (Poffset), for the low RPT .

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4. REMOTE OPERATION

4.3.3

Error Messages

molbox1+ always replies to a command. If the command is incorrect or contains invalid data,
an error number is returned in the form “ERR# n” where n is an integer number that
represents a specific error. This allows for easy error trapping by the host computer.
Table 31 is a list of the possible error numbers and the error description for each.
Table 39. Error Messages
REPLY

DESCRIPTIONERROR"The molbox1+ is in high security level and cannot accept
remote commands""OK""molbloc flow is too great""Text argument is too long""User defined coefficient cannot be 0""External device not detected""External device improperly configured""Numeric argument missing or out of range""Missing or improper command argument(s)""External device timeout error""Unknown command""MFC not defined or selected""Command missing argument""System overpressured""Text detected in numeric field""User unit not defined""Averaging cycle not started""MFC Malfunction""Selected gas not available""Command not yet available""User device not defined""Pressure is not stable""Option not available or installed""molbloc not detected""RPT out of calibration""COM port failed to initialize""Internal device #1 timeout error""Internal device #2 timeout error""Busy averaging""Fatal mass flow calculation error""molbloc EEPROM is full""molbloc gas not found""molbloc is write protected""molbloc write error""MFC unit mismatch""Incompatible device detected"""Selected range not available""molbloc verify error""molbloc read error""molbloc invalid""PRT measurement error""Incorrect MFC mode""Entry already exists""Argument(s) not allowed""The leak is too large""Temperature change was too great""Offset was excessive. Check tare""Possible upstream leak"

ERR# 0
ERR# 1
ERR# 2
ERR# 3
ERR# 4
ERR# 5
ERR# 6
ERR# 7
ERR# 8
ERR# 9
ERR# 10
ERR# 11
ERR# 12
ERR# 13
ERR# 14
ERR# 15
ERR# 16
ERR# 17
ERR# 18
ERR# 21
ERR# 22
ERR# 23
ERR# 24
ERR# 25
ERR# 26
ERR# 27
ERR# 28
ERR# 29
ERR# 30
ERR# 31
ERR# 32
ERR# 34
ERR# 35
ERR# 36
ERR# 37
ERR# 38
ERR# 39
ERR# 40
ERR# 41
ERR# 42
ERR# 43
ERR# 44
ERR# 45
ERR# 46
ERR# 47
ERR# 48
ERR# 49

Page 115© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALERR# 50
ERR# 51
ERR# 52
ERR# 53
ERR# 54
ERR# 55

4.3.4"Possible downstream leak""Possible bypass leak""Not available in AB mode""Suffix not allowed""Suffix missing or out of range""Not Ready"Command Descriptions

Each command description gives the full syntax showing usage. Ranges of parameters or
parameter types are indicated. There are 2 types of commands. The Common and Status
Commands support IEEE Std. 488.2, while the molbox1+ commands access all other functions.

4.3.4.1

IEEE Std. 488.2 Common and Status Commands

The molbox1+ supports a set of commands that are common to all instruments
conforming to IEEE Std. 488.2 protocol. Though defined by the IEEE-488.2 standard,
they also apply to molbox1+ RS232 (COM1) communications. These commands
make it easy to perform basic functions for any device that supports them.
These command also cover the status reporting commands. Refer to Section 4.4
for details on the status registers mentioned in these commands. Query forms ofthese commands must be followed by a question mark and IEEE-488.2 Common
Commands always start with an asterisk (“*”). Unlike the other molbox1+
commands, they must have a space instead of an equals sign (“=”) between thecommand and any arguments. Also unlike the other molbox1+ commands, if you
are using the IEEE-488 port, the query form (command is immediately followed
by a “?”) must be used to get a reply. If using the COM1 port and the commandis not a query, “OK” will be replied.
∗CLS
Purpose
SyntaxRemarks

Example∗ESE(?)
Purpose
SyntaxParameters

Query Reply
Remarks

Example∗ESR?
Purpose
SyntaxQuery Reply
RemarkExample© 2010 Fluke Calibration

Clear all of the status and event structures.
“∗CLS”
This program message clears the following evens and status registers:
Standard Byte Register (STB)
Standard Event Status Register (ESR)
Error Queue
Pending OPC operations
Command:“*CLS”
Reply:“OK” (using COM1. No reply if IEEE-488 port)

Read or set the Standard Event Status Enable Register.
“∗ESE n”“∗ESE?”n:’0 to 255’. This is the decimal representation of the bit(s) toenable. To enable the PON and QYE bits, the argument would
be 128 + 4 = 132.
n (0 to 255)
The Standard Event Status Enable register determines which bits in the standard
Event Status Register are enabled and included in the Status Byte Register (ESBbit), and can assert the SRQ line. The reply is in decimal numeric form.
Command:“*ESE 132”
Reply:“OK” (using COM1. No reply if IEEE-488 port)
Command:“*ESE?”
Reply:“132”
Read the Standard Event Register.
“∗ESR?”n (0 to 255)
The Standard Event Register contents are cleared after reading. The reply is indecimal numeric form.
Command:“*ESR?”
Reply:“4”

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4. REMOTE OPERATION∗IDN?
Purpose
SyntaxRemarks

Query Reply
Example∗OPC(?)
Purpose
SyntaxRemarks

Query Reply
Example∗OPT?
Purpose
SyntaxRemarks
Query Reply
Example∗RST
Purpose
SyntaxRemarks

Example∗SRE(?)
Purpose
SyntaxParameters

Remarks

Query Reply
Example∗STB?
Purpose
SyntaxRemarks
Query Reply
ExampleIdentify the molbox1+ version, range, and serial number.
“∗IDN?”The identification reply is made up of the manufacturer, the model, the serial
number, the internal RPT serial numbers and the software version. Each isseparated by a comma.
The version string.
Command:“*IDN?”
Reply:“FLUKE, molbox1+, 620-84836-85056, Ver6.00-ngmgl”
Sets the operation complete bit when all operations have completed.
“∗OPC”“∗OPC?”
This command enables the molbox1+ to set the OPC bit in the Standard Event
Status Register when it has completed all pending functions. The Query replies
with a “1” when all functions are complete.
Since the molbox1+ does not support overlapping commands, this command has
no practical use.
“0” or “1”Command:“*OPC”
Reply:“OK” (using COM1. No reply if IEEE-488 port)
Command:“*OPC?”
Reply:“1”
Reads the list of installed molblox1 options.
“∗OPT?”
This Query returns any registered option(s) installed in the molbox1+.
option is separated by a comma.
A comma delimited text field of the installed options.
Command:“*OPT?”
Reply:“NONE” (no options installed)

Each

Resets the molbox1+ settings to factory settings.
“∗RST”
This command sets the molbox1+ settings to factory settings which is equivalent
to pressing [SPECIAL] on the front panel and selecting <5Reset>, 1sets. This
does not affect the communications settings.
Command:“*RST”
Reply:“OK” (using COM1. No reply if IEEE-488 port)
Read or set the Service Request Enable Register.
“∗SRE n”“∗SRE?”n:‘0 to 255’. This is the decimal representation of the bit(s) toenable. To allow the MAV and ESB bits to assert the SRQ line,
the argument would be 32 + 16 = 48. Bit 6 (64) is reserved andcannot be set.
The Service Request Enable Register determines which bits of the Status Byte
can set the MSS bit of the Status Byte and request service by asserting the SRQ
line of the IEEE-488 interface.
n (0 to 255)
Command:“*SRE 48”
Reply:“OK” using COM1. No reply if IEEE-488 port)
Command:“*SRE?”
Reply:“48”
Read the Status Byte Register.
“∗STB?”The Status Byte Register reflects the general status of the molbox1+. The ‘MSS’
bit state is represented by bit 6.
n (0 to 255)
Command:“*STB?”
Reply:“4”

Page 117© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL∗TST?
Purpose
SyntaxRemarks

Query Reply
Example4.3.4.2#
Purpose
SyntaxArguments
Remarks

ExampleABORT
Purpose
SyntaxRemarks

ExampleSee Also
AIRW(=)
Purpose
SyntaxDefault
Arguments
Remarks
ExampleErrorsSee Also© 2010 Fluke Calibration

Read the power on self test status.
“∗TST?””The molbox1+ system memory stores the user settings (units, mode, resolution)and retains them when the unit is shutoff. On power up, this memory is checked.
If this memory is corrupted, all user settings are reset to default (as if the “∗RST”
program message was executed), and the ∗TST query returns a ‘1’. If themolbox1+ passed the test on power up OR if the ∗TST query was used at least
once since the unit was powered up the reply is ‘0’.
“0” or “1”Command:“*TST?”
Reply:“1”molbox1+ commands
To allow the Host computer to communicate with a device connected to themolbox1+ COM2 port.
“#XX”
xx:
The string to send out of the COM2 port. It must be less than
40 characters long.
The molbox1+ COM2 port can be used to communicate to another RS232 device(e.g., another molbox1+ or a multimeter). This allows the user to use one COM
port or IEEE-488 port on the host computer to communicate with the molbox1+
and another device. A carriage return and a line feed (<CR><LF>) are added tothe string.
After this command is issued, the molbox1+ will reply back the first string received
by the molbox1+ COM2 port that is terminated with a carriage return. Line feeds
are discarded. This will discontinue when the next command is sent to themolbox1+.
There is no other reply from this command. Prior to using this command, youmust ensure that the molbox1+ COM2 port is correctly set up to communicate
with the device. Refer to the “COM2=“ command.
Command:“#VER”
Reply:“FLUKE, molbox RFM Ver1.20”
To stop an active averaging, tare, purge, leak check cycle, or reset the list of gas
calibrations on a molbloc.
“ABORT”
This command should be used to ensure that molbox1+ in a known state. The
tare, purge, and leak check cycles put the molbox1+ into a condition where it is
not usable for normal flow measurement, so the “ABORT” command should be
used before general operation of the unit begins if the previous state of the unit is
not known. The “ABORT” command also clears out any previous leak or tarecycle errors. If the “GASCALS” command is used to list the calibrated gases on amolbloc, the “ABORT” command resets the list back to the beginning.
Command:“ABORT”
Reply:“ABORT”“FA”, “TARESETUP”, “LEAKCK”, “PURGE”, “GASCALS”
Read or set the humidity ratio for the gas, AIR.
“AIRW=HumidityRatio”“AIRW”“AIRW=0.00
00”
HumidityRati
The humidity ratio (0-0.1)
o:The humidity ratio is only used if the gas is set to specify AIR. For all other gas
types, the ratio is ignored.
Command:“AIRW=.01”
Reply:“0.0100”
ERR# 6:The humidity ratio is invalid.
3.2.2, 3.4.2.2“GAS”

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4. REMOTE OPERATION

ALLR
Purpose

SyntaxRemarks

ExampleErrorsSee Also

Read the next ready/not ready indication, measurement of molbloc flow, themolbox1+ upstream and downstream RPT pressure values and the molbloc
temperature.
“ALLR”The next available measurements are replied. This can take up to 1 second,since the molbox1+ waits for the next flow measurement before replying. The
reply starts with the flow ready information. Then the flow value is given in thecurrent flow units. Commas are then used to separate the other measurements inthis order:“RDY flow, avgpres, uppres, dnpres, temp”.
“RDY” is the flow ready field. The ready status is covered in the “SR” command.
“flow” is the current measured flow and flow units. “-999999” in this field whenusing a molbloc-S indicates that the BPR is too low for a correct flow
measurement.
“avgpres” is the average of the upstream and downstream RPTs and units.
“uppres” is the upstream RPT pressure measurement and units.
“dnpres” is the downstream RPT pressure measurement and units.
“temp” is the molbloc temperature and units.
Command:“ALLR”
Reply:“R
0.00075 slm,97.3844 kPa,97.3945 kPa,97.3743 kPa,17.97C”
Reply:“NRP -999999 slm,97.3844 kPa,97.3945 kPa,97.3743 kPa,17.97C” (BPR too low)
ERR# 27 or One of the RPTs (pressure transducers) is not functioning.
28:
3.1.2.2, “SR”, “READYCK”, “DP”, “PRHI”, “PRLO”, “FR”, “TEMP”

AUTOZERO(=)
PurposeRead or set the status of the reference pressure transducer (RPT) AutoZ function.
Command“AUTOZERO=n”
Query“AUTOZERO”
Default“AUTOZERO=1”
Argumentsn:’0’ Autozero OFF’1’ Autozero ON
Remarks
The molbox1+ “AutoZ” function can be turned ON and OFF. This command sets
the AutoZ status for both of the internal RPTs.
ExampleSent:“AUTOZERO=1”
Query reply:“AUTOZERO=1”
Errors
ERR# 6:
The argument was other than a ‘0’ or a ‘1’.
See Also
3.4.4.4, “ZOFFSET:XX”
BEEPER(=)
Purpose
SyntaxArguments
Remarks
ExampleTo actuate the internal buzzer for half of a second.
“BEEPER”“BEEPER=freq”
freq:This variable has no purpose, but is included for compatibility
with the DH Instruments RFM product.
The internal buzzer tone is fixed, so the argument serves no purpose.
Command:“BEEPER=1000”
Reply:“1000”

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALBPR(=)
PurposeCommand:Query:
Defaults
Arguments

Remarks

ExampleErrorsSee Also
CIN
Purpose
SyntaxRemarks

ExampleSee AlsoCOMn(=)
Purpose
SyntaxArguments

Defaults
Remarks

ExampleError
See Also
DATE(=)
Purpose
SyntaxArguments

ExampleErrorsSee Also© 2010 Fluke Calibration

Read or set the back pressure ratio (BPR) mode. This is only available whenusing a molbloc-S.
“BPR =mode”“BPR=mode, suspend“BPR”“BPR=2,0”
mode:‘0’ BPR is kept “OFF”‘1’ BPR is kept “ON”
‘2’ BPR is in “auto” mode.
suspend:‘0’ BPR normal operation‘1’ BPR function is suspended, left in the current condition until
set back to normal operation.

The BPR mode determines the operation when the back pressure ratio ismeasured when using molbloc-S to measure flow. The optional “suspend”
argument can be used to leave the BPR valve state in its current condition,
allowing manual manipulation of the molbox1+ valves without the BPR function
intervening. If the “suspend” argument is not given, it is presumed to be ‘0’ fornormal BPR operation.
Sent:“BPR=2”
Reply:“2, 0”
Sent:“BPR=1,1”
Reply:“1, 1”
ERR# 6:
One of the arguments is out of range.
3.6.9
Read the MFC measurement current if in ‘mA’ mode.
“CIN”
The optional MFC interface can measure current output of an MFC. The
molbox1+ must be in ‘mA’ mode before this can be done (see the “MFCCH”
command). The returned data is always in “mA”.
Command:“CIN”
Reply:“5.34 mA”
3.2.8
To set or read the configuration of the COM1 or COM2 ports.
“COMn=baud,parity,data,stop”“COMn”n:
The COM port: ‘1’ or ‘2’.
Baud:
The baud rate. This may be ‘300’, ‘600’, ‘1200’, ‘2400’, ‘4800’,‘9600’ or ‘19200’.
parity:The data parity. This may be ‘O’ for odd, ‘E’ for even or ‘N’ for
none.
data:
The data word length. This may be ‘7’ or ‘8’.
stop:
The number of stop bits. This may be ‘1’ or ‘2’.
“COM1=2400,E,7,1”“COM2=2400,E,7,1”
The COM1 port is used to communicate to the molbox1+. When the COM1 port
configuration of the molbox1+ is changed, the command reply will be sent at the
old COM1 settings, but all subsequent communications will be accomplished at
the new COM1 settings.
The COM2 port is used to allow commands to be passed through the molbox1+ toa device connected to the COM2 port (refer to the ‘#’ command).
Command:“COM1=9600,N,8,1”
Reply:“9600,N,8,1”
ERR# 7:
Missing or improper command argument(s).
3.6.6.1
Read or set the internal clock date.
“DATE”“DATE=yyyymmdd
yyyy:
The year from 1980 to 2079.
mm:
The month from 1 to 12.
dd:
The day from 1 to the last valid day of the given month.
Command:“DATE=19981005”
Reply:“19981005”
ERR# 6:
The time date is invalid.
3.6.5.3

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4. REMOTE OPERATION

COUT(=)
Purpose
SyntaxArguments
Defaults
Remarks

ExampleSee Also
DEVICE(=)
Purpose
SyntaxArguments

Defaults
Remarks

ExampleErrorsSee AlsoDP
Purpose
SyntaxRemarks

ExampleSee Also
DRVn(=)
Purpose
SyntaxArguments

Defaults
Remarks
ExampleErrorsSee Also

Set a current to the MFC if in current mode.
“COUT=current”
Current:
The current to be sent to the MFC (4 to 20 mA).
“COUT=4”
The optional MFC interface can set a current for an MFC. The molbox1+ must be
in current mode before this can be done (see the “MFCCH” command). The datais always in “mA”. This command does not change the regulation mode target for
the MFC.
Command:“COUT=12”
Reply:“12.00 mA”
3.4.8
Select to use the ‘A’, ‘B’ or both the ‘A’ and ‘B’ molblocs.
“DEVICE=n”“DEVICE”
Device:‘A’ to select molbloc A.
‘B’ to select molbloc B.
‘A+B’ to select molbloc A and B in A+B mode.
‘EXT’ to reload molbloc A and molbloc B data.
“DEVICE=A”
The molbloc calibration data is stored in the external molbloc. This data isnormally loaded on power up, but can be reloaded using this command if themolbloc has been changed since power up. Loading the data normally takes lessthan a second, but can take up to 10 seconds if the molbox has problems
communicating with the molbloc. When using molbloc-S, A+B mode cannot be
selected if “BPR” mode is set to “auto”
Command:“DEVICE=B”
Reply:“B”
ERR# 6:
BPR is in auto mode and “A+B” mode was requested
ERR# 7:
Text argument in invalid
ERR# 24:A molbloc is not connected to the molbox1+.
ERR# 35:
The molbloc experienced a communications timeout.
ERR# 40:
The molbloc experienced a read checksum failure.
ERR# 41:
The molbloc data header is corrupted.
3.1.1
Read the differential pressure value used by molbox1+ to calculate flow.
“DP”
The molbox1+ has upstream and downstream absolute RPTs. The pressure
returned by this command is the differential pressure value that is being used bymolbox1+ to calculate flow. This is the tare adjusted difference between the 2absolute RPTs. The first 3 characters of the reply from molbox1+ make up the
Ready/Not Ready condition (see the “SR” command). The differential pressure
string follows it.
Command:“DP”
Reply:“R
0.0227 kPa”
“SR”
Read or set the status of an external solenoid valve.
“DRVn=x”“DRVn”N
The valve to operate on. This can be from 1 to 8.
X
The state to change the valve to. ‘0’ to de-activate it. ‘1’ toactivate it.
“DRVn=0”
The molbox1+ has the option of controlling up to eight external valves.
Command:“DRV3”
Reply:“DRV3=1”
ERR# 6:
The n or x arguments are not within given limits.
3.6.7, 7.2

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ERR
Purpose
SyntaxRemarks

ExampleSee AlsoFA=
Purpose
SyntaxArguments
Remarks

ExampleErrorsSee Also
FCOEF
Purpose
SyntaxRemarks

ExampleSee Also
FR
Purpose
SyntaxRemarks

ExampleErrorsSee Also© 2010 Fluke Calibration

Read the last error message.
“ERR”
The “ERR” command provides more details about an error that has occurred. If
the user receives an “ERR# nn” reply, the “ERR” command returns a brief
description about the last error number that was replied.
Command:“ERR”
Reply:“Missing or improper command argument(s)”4.3.3, “*CLS”
Start a single flow averaging cycle.
“FA=period”
period:The averaging period in seconds(from 20 to 999 seconds if A+B mode, otherwise 4-999 seconds).
This command is used to start an averaging period that results in the averagemolbloc flow, MFC measurement, and standard deviation of the molbloc flow overthis period. After sending this command you can monitor the averaging cycle byusing the “FR” or “SR” command to determine when the averaging cycle iscomplete. Once the cycle is done, you must use the “FRA” command to collect
the results.
Command:“FA=20”
Reply:“20 s”
ERR# 6:
The period argument is not within the specified limits.
3.4.6.2 , “FR”, “SR”, “FRA”, “ABORT”
Read the coefficient that converts kg/s to the current flow units.
“FCOEF”
The flow coefficient is a value that is used to convert kg/s to the current flow units.
It is dependent on the current flow unit and the gas selected. To use thiscoefficient, multiply it by kg/s to get flow in the current flow units.
Command:“FCOEF”
Reply:“4.798073e+004”
3.4.3, 7.1.3
Read the next measurement of flow through the molbloc as calculated by themolbox1+.
“FR”
The next available flow value is read in the current flow units. This can take up to
1 second, since the molbox1+ waits for the next flow measurement before
replying. The reply also contains ready information.
The first 3 characters are reserved for the ReadyNot Ready status. The
Ready/Not Ready status is covered in the “SR” command.
The flowmeasurement number starts at the fifth character, and is followed by the flow
units.
Command:“FR”
Reply:“R
0.00001 sccm”
ERR# 27:
One of the RPTs (transducer) is not functioning.
“BUSY”The molbox1+ is busy calculating an A+B flow value.
3.1.3 , “SR”, “READYCK”, “ALLR”

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4. REMOTE OPERATION

FRA
Purpose
SyntaxRemarks

Read the results of a completed flow averaging cycle.
“FRA”
This command is used to check on the status of or collect the results of an
averaging cycle that was started earlier using the "FA=" command. During the
averaging cycle, this command will reply "BUSY" until the averaging cycle iscomplete. Then the reply will be the results of the averaging cycle. If the cycle isaborted before it is complete (see "FA="), then the data will be lost.
The data that is returned from the command consists of multiple numeric fields
delimited by commas. The flow numbers are in the current flow unit of measure.
The actual data fields returned are as follows:
An "H" will appear as the first character of the reply string. An "S" will appear as
the second character of the string if the flow stability stayed within the stability
setting during the sequence. From the fourth position on the numeric data fields
are:
Average flow over the averaging period.
Standard deviation of flow over the averaging period.
The minimum flow reached during the period.
The maximum flow reached during the period.
The MFC voltage or current target or “NA” if MFC option not enabled.

ExampleErrorsSee Also
FUNIT(=)
Purpose
SyntaxDefaults
Arguments
Remarks

ExampleErrorsSee Also

The MFC voltage or current average measurement or “NA” if MFC option notenabled.
Command:“FRA”
Reply:“HS 0.00002 sccm,0.00000,0.00002,0.00002,0.5000 V,0.1203 V”
Reply:“HS 0.00002 sccm,0.00000,0.00002,0.00002,NA, NA” (MFC
disabled)“BUSY” if still averaging
ERR# 15:The “F=” command was not sent previous to this command.
3.4.6.2, “FR”, “SR”, “FA”

Read or set the unit of measurement for the flow through the molbloc as
calculated by the molbox1+.
“FUNIT=unit”“FUNIT”“FUNIT=sccm”
unit:
The flow unit used to display the measured flow.
The flow unit displayed can be changed using this command. The flow unit mustbe supported by the molbox1+. The flow unit protocol is the same as the front
panel flow unit definitions.
Command:“FUNIT=SLM”
Reply:“SLM”
ERR# 7:
The flow unit is invalid or not supported by the molbox1+.
3.4.3, “UTEMP”, “VLM”

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALGAS(=)
Purpose
SyntaxArguments
Remarks

ExampleErrorsSee Also

Read or set the gas type being flowed through the molbloc.
“GAS=gas“GAS”
gas:
Specify the gas to use.
The calibration for the gas type being flowed through the molbloc is specified
using this command. The gas must be supported by the molbox. The gas typeprotocol is the same as the front panel gas definitions. A valid molbloc must beconnected to the molbox1+ before changing the gas type. If several calibrations
exist for the given gas, then the “default” calibration for the gas specified will be
used. If a calibration for the specified gas does not exist, then the molbloc’s
default calibration will be used. The “GASCAL” command can be used to querywhat calibration is being used. The “GASCAL” command can also be used to
specify the exact calibration to use if multiple calibration exist for a specific gas..
Command:“GAS=N2”
Reply:“N2”
ERR# 7:
The gas is invalid for the molbox1+.
ERR# 24:A molbloc is not connected to the molbox1+.
ERR# 32:
This gas is not supported by the molbox1+.
ERR# 35:
The molbloc experienced a communications time out.
ERR# 39:
The molbloc experienced a data verification failure.
ERR# 40:
The molbloc experienced a read checksum failure.
ERR# 41:
The molbloc data header is corrupted.
3.4.2, “AIRW”

GASCAL(=)
PurposeCommandQuery
Default
Arguments

Remarks

ExampleErrorsSee Also© 2010 Fluke Calibration

Read or set the active molbloc calibration to use.
“GASCAL=gas (, calname)”“GASCAL”“GASCAL=N2”
gas:
Calibration gas.
Calibration name (optional. Same as gas assumed if blank or
calname:ignored if molbloc does not have named calibrations)
A molbloc can contain multiple calibrations, possibly for each gas. The calibration
should be selected before use. This command selects the desired calibration byreferring to the calibration gas, and optionally by the unique name given to thecalibration for that gas if the molbloc supports multiple calibrations. The“GASCALS” command should be used prior to the “GASCAL” command to
determine what calibrations are available in the molbloc..
Sent:“GASCAL=HE, LOP”
Query reply:“HE, LOP”
Sent:“GASCAL=HE”(calname not given so “HE” is assumed)
Query reply:“HE, HE”
ERR# 2:
The gas or calibration name given is too long.
ERR# 24:A molbloc is not connected to the molbox.
ERR# 32:
The calibration was not found.
ERR# 35:
The molbloc experienced a communications time out.
ERR# 40:
The molbloc experienced a read checksum failure.
“GASCALS” command“GAS” command

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4. REMOTE OPERATIONGASCALS
PurposeQuery:
Remarks

List out the calibrations in an active mobloc..
“GASCALS”
All of the calibrations in an active molbloc created with molbox version 6.00 or
greater can be listed one at a time using the GASCALS command. You MUST
first send the ABORT command to “reset” the listing of the calibrations, then send
the “GASCALS“ command to get each calibration until there are no morecalibrations. Here are the 4 fields that are returned for each calibration found:
Calibration gas:
Calibration name:Calibration range:
Attributes:

ExampleErrorsSee Also

ID(=)
Purpose
SyntaxDefault
Arguments
Remarks

ExampleSee Also
KFACT(=)
Purpose
SyntaxArguments
Defaults
Remarks
ExampleSee Also

The name of the gas for this calibration. This is one of theknow gas types supported by the molbox
The unique name for this calibration. (Only present on
molblocs with named calibrations)
The range and range unit for this calibration. (Only present
on molblocs with named calibrations)
Each calibration has several attributes. These attributes arereported as a sum of the possible attribute values (Onlypresent on molblocs with named calibrations):‘1’ NOT a default calibration. Default calibrations are used
when the “GAS=” command is used to specify whichcalibration to use using just the gas name. Thiis
attribute when set indicates that this is NOT a default
calibration‘4’ Calibration is a “premium” calibration.
‘8’ Calibration is a “downstream” calibration.

Sent:
Reply:“GASCALS”“He, LOP ,1 slm, 0”
Named default calibration“He, LOP ,1 slm, 4”
Default premium calibration“He, LOP ,1 slm, 6”
Default premium calibration. Other He
calibration exist on this molbloc“He”
molbloc does not supports named calibrations
ERR# 32:
No more calibrations exist in the molbloc.
”ABORT” command”GAS” command”GASCAL” command

Read or set the user defined identification label.
“ID=string”“ID”“ID=NONE”
String:An alphanumeric string up to 12 characters wide.
The user defined ID label can be used to allow the user to “tag” the molbox1+ witha unique identifier. This ID is stored in non-volatile memory and cannot be erased
by a power failure, system fault or reset.
Command:“ID=molbox-001”
Reply:“molbox-001 ”
3.6.5.2
Read or set the molbox1+ K factor.
“KFACT=kfactor”“KFACT”
Kfactor:The new “K” factor.
“FACT=1.0” (Disabled)
The “K” factor is set to 1 for normal operation.
Command:“KFACT”
Reply:“1.000000”
3.4.1

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALLEAKCK(=)
Purpose
SyntaxArguments

Remarks

ExampleErrorsSee Also
LOCAL
Purpose
SyntaxRemarks
ExampleSee Also
MEM
Purpose
SyntaxRemarks

Example© 2010 Fluke Calibration

Starts a molbox1+ or system leak check cycle or checks if a cycle is complete.
“LEAKCK=type”“LEAKCK”
type:“BOX”. Starts a leak check cycle on the molbox1+ internal
circuit. The molbox must be prepared for the leak check by
setting pressures and venting ports before the leak check is
executed.
“SYS”. Starts a leak check cycle on the system connected to themolbox1+. The system must be prepared for the leak check by
setting pressures and operating valves before the leak check is
executed.
This command is used to start and monitor the progress of the leak check. Both“BOX” and the “SYS” leak checks take 60 seconds to complete. At the end of theleak check, the molbox1+ is returned to its normal operating state.
The “ABORT” command can be used to stop a leak check cycle, clear out any
previous error messages, and return the molbox1+ to its normal operating state.
While the leak check cycle is executing, a ‘b’ (“busy”) will appear in the 3rd
character position of the “FR” and the “SR” command replies.
If the leak check failed, an error will be replied to the “LEAKCK” query until the“ABORT” command is used to abort the leak check. When the leak check hascompleted without an error, the “LEAKCK” query will reply “OK”.
If a molbloc-S is active and a “SYS” type leak check was run, the reply is theactual average leak rate (in the current pressure units) during the leak check.
The “LEAKCK” command must be completed or aborted using the “ABORT”
command before performing other operations.
Command:“LEAKCK=BOX,1”
Reply:“BOX” (starting new molbox1+ leak check cycle including the
microrange RPT)
Command:“LEAKCK=SYS”
Reply:“SYS” (starting new system leak check cycle)
Command:“LEAKCK”
Reply:“23 sec” A leak check cycle is currently running. This is thenumber of seconds remaining in the test.
Reply:“OK” (The leak check cycle has completed)
Reply:“0.3412 kPa/s” if a molbloc-S is active and the “SYS” type leakcheck has been completed.
ERR# 6:
One of the arguments is not invalid.
ERR# 15:
A leak check cycle has not been started.
ERR# 46:
A large leak exists.
ERR# 47:
The temperature changed too much to test for a leak.
ERR# 48:
The absolute RPT disagreement too great to test for a leak.
ERR# 49:
Possible upstream leak.
ERR# 50:
Possible downstream leak.
ERR# 51:
Possible bypass leak.
3.4.4.3, “ABORT”
Enable the front panel controls if in remote and go to local mode.
“LOCAL”
In LOCAL mode, all front panel operations are available. The LOCAL command
deactivates REMOTE mode.
Command:“LOCAL”
Reply:“LOCAL”“REMOTE”
Read the memory test status.
“MEM”
On power up a memory test is run to check the integrity of the internal data NVRAM.
If the memory has been corrupted, "FATAL MEMORY FAULT" will be displayedon power up to alert the user, and the memory test status command will return a ‘0’.
The command will return a ‘1’ if the memory is OK.
Command:“MEM”
Reply:“0”

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4. REMOTE OPERATION

MFCCH
Purpose
SyntaxDefaults
Arguments

Remarks
ExampleErrorsSee Also

Read or set the MFC channel and output mode (voltage or current).
“MFCCH=channel,mode”“MFCCH”“MFCCH=1,v”
channel:The optional MFC switchbox channel.
0
disables the MFC interface.
1enables the optional MFC interface.
1 to 5selects the MFC channel to use for optional MFC
switchbox
mode:
The MFC interface mode‘v’
Voltagecontrolandmeasuremode.
The selected channel will be used for voltage‘mA’setting and measuring.
Current loop control and measure mode.
The selected channel will be used for current‘ ‘
loop setting and measuring.
If the argument is not given, the molbox will use
the selected channel to measure the voltage,
and will always use channel 1 to set the voltage.
This is used to measure voltage MFM’s that areconnected to channel 2 through 5 with an MFC
controlling on channel 1.
The optional MFC interface can support voltage or current controlled MFC’s.
There is also an available MFC switchbox, which is controlled by the molbox1+.
Command:“MFCCH=1,
Enables MFC for current
mA”
Reply:“1,mA”
Command:“MFCCH=3,
Enables MFC on switchbox channel 3 for volts
V”
Reply:“3,V”
Command:“MFCCH=0”
Disables MFC interface
Reply:“0,V”
Command:“MFCCH=1,
Enables MFC control on channel 1
V”
Reply:“1,V”
Command:“MFCCH=4”
Enables MFM input on channel 4
Reply:“4,V”
ERR# 6:
Channel or mode arguments are invalid
ERR# 23:
The MFC option is not installed
ERR# 23:
Channel greater than 1 and MFC switchbox option is not installed
3.4.8, 7.3

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

MOLBLOC
Purpose
SyntaxRemarks

ExampleErrorsSee Also
OHMS
Purpose
SyntaxRemarks
ExampleSee Also
PCAL(=)
Purpose
SyntaxDefaults
Arguments

Remarks
ExampleErrorsSee Also© 2010 Fluke Calibration

Read the active molbloc header data. This command does NOT load molbloc
information into the molbox1+, it only accesses previously loaded information.
“MOLBLOC”
The external molbloc header data includes the serial number, range, calibration
date, and PRT calibration data. This data is stored in the molbloc, and isdownloaded to the molbox1+ on power up. The data for the active molbloc isreturned in a single, comma delimited string in the following order:
Serial Number
Range Designator
Range Flow Units
Gas
Calibration Date (yyyymmdd)
Total PRT Resistance (upstream + downstream) at 0 °C [Ω]PRT Slope [dimensionless]
Upstream PRT Resistance at 0 °C [Ω]Downstream PRT Resistance at 0 °C [Ω]molbloc-S nozzle Serial Number if the molbloc is a “-S” or same as themolbloc serial number if a the molbloc is a “-L” molbloc.
“S”, “L”, or “L7” depending on whether the molbloc is a “-S” or “-L”. The “L7”designation indicates the molbloc is using NIST based gas property data.
“MOLBLOC”
Command:“100, 1.00, sccm, N2, 19980426, 200.0050, 0.7792, 100.0010,
Reply:
100.0040, 100, L”(molbloc-L with original gas property data)“100, 1.00, sccm, N2, 19980426, 200.0050, 0.7792, 100.0010,
Reply:
100.0040, 100, L7” (molbloc-L with NIST based gas properties)
100, 1.00, sccm, N2, 19980426, 200.0050, 0.7792, 100.0010,
Reply:
100.0040, 120, S”(molbloc-S)
ERR# 7:
The gas is invalid with the molbox1+.
ERR# 24:A molbloc is not connected to the molbox1+.
ERR# 35:
The molbloc experienced a communications timeout.
ERR# 40:
The molbloc experienced a read checksum failure.
ERR# 41:
The molbloc data header is corrupted.
3.5.1, “DEVICE”

Read the most recent measurement of the active molbloc’s two PRTs.
“OHMS”?????
Sent:“OHMS”
Reply:“109.031 Ohms, 109.037 Ohms”
5.4, 3.4.5, “TEMP”
Read or set the user RPT calibration adjustments (PA, PM).
“PCAL=upadder, upmult, dnadder, dnmult”“PCAL”“PCAL=0, 1.00000, 0, 1.00000”
Upadder:
The upstream RPT calibration adder (PA) from –10,000 to
10,000 Pa.
Upmult:The upstream RPT calibration multiplier (PM) from 0.9 to 1.1.
Dnadder:
The downstream RPT calibration adder from –10,000 to
10,000 Pa.
Dnmult:
The downstream RPT calibration multiplier from 0.9 to 1.1.
Mradder:
The optional microrange RPT calibration adder from –10,000 to
10,000 Pa.
The user defined pressure calibration for the upstream and downstream RPTs
can be access with this single command. The adder is always in Pascal.
Command:“PCAL=38, 1.0021, 14, .9942”
Reply:“ 38.00 Paa, 1.002100, 14.00 Paa, 0.994200”
ERR# 6:
Invalid argument.
5.2

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4. REMOTE OPERATIONPCALDATE(=)
PurposeRead or set the user RPT calibration dates.
Syntax“PCALDATE=yyyymmdd, yyyymmdd”“PCALDATE”
Defaults“PCALDATE=19980101,19980101
Arguments
yyyy:
The year from 1980 to 2079.
mm:
The month from 1 to 12.
dd:
The day from 1 to the last valid day of the given month.
Remarks
The user defined pressure calibration dates for the upstream and downstream
RPTs can be access with this single command in this order.
ExampleCommand:“PCALDATE=19981005, 19981005”
Reply:“19981005, 19981005”
Errors
ERR# 7:
One or more of the date(s) are invalid.
See Also
5.2, “PCAL(=)”
PCOEF
Purpose
SyntaxRemarks

ExampleSee Also
PR
Purpose
SyntaxRemarks

ExampleSee Also
PRHI
Purpose
SyntaxRemarks
ExampleSee Also
PRLO
Purpose
SyntaxRemarks
ExampleSee Also
PUNIT(=)
Purpose
SyntaxDefaults
Arguments

Remarks
ExampleErrorsSee Also

Read the coefficient to convert Pascal [Pa] to the current pressure units.
“PR”
The pressure coefficient (PCOEF) is a value that is used to convert Pascal units
to the current pressure units. To use this coefficient, multiply it by pressure in
Pascal to get pressure in the current units.
Command:“PCOEF”
Reply:“1.000000e-003”
3.5.8, 7.1.1, “PUNIT”
Read the next molbloc average pressure.
“PR”

 upstream − downstream pressure value is read in2

The next available average 

the current pressure units. It is the average of the tare corrected upstream andthe downstream transducers.
The data string also contains flow readyinformation, and the pressure units.
The first 3 characters of the reply are reserved for the flow ReadyNot Ready status.
The Ready/Not Ready status is covered in the “SR” command. The pressure
measurement number starts at the fifth character, and is followed by the pressure
unit of measure.
Command:“PR”
Reply:“R
247.5982 kPa a”“READYCK”, “SR”, “DP”, “PRHI”, “PRLO”. “ALLR”
Read the last measured upstream absolute pressure (tare corrected).
“PRHI”
The current upstream pressure value (corrected for tare) is returned in the current
pressure unit of measure.
Command:“PRHI”
Reply:“247.56 kPaa”“DP”, “PR”, “PRLO” . “ALLR”
Read the last measured downstream absolute pressure (tare corrected).
“PRLO”
The current downstream pressure value (corrected for tare) is returned in thecurrent pressure unit of measure.
Command:“PRLO”
Reply:“224.67 kPaa”“DP”, “PR”, “PRHI” . “ALLR”
Read or set the pressure display unit of measure.
“PUNIT=unit”“PUNIT”
unit:
The text corresponding to the pressure unit of measure. The
pressure unit protocol is the same as the protocol used for front
panel entries and displays.
This command determines what unit of measure is used to display pressure.
Command:“PUNIT=KPA”
Reply:“kPa a”
ERR# 7:The unit is invalid.
3.5.8

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALPURGE(=)
Purpose
SyntaxArguments
Remarks

ExampleErrorsSee Also
RANGE
Purpose
SyntaxRemarks

ExampleSee Also
RATE
Purpose
SyntaxRemarks
ExampleSee Also
RE
PurposeRead the range designation of the active molbloc.
“RANGE”
The range designation of the active molbloc is returned in the flow units used todefine the range. Note that the effective molbloc range is dependent on the gas
being flowed and the molbloc pressure dependent calibration type. Do notassume the usable range is equal to the range designation.
Command:“RANGE”
Reply:“10.00 sccm”
1.2.5, 3.5.1, Table 23, Table 24, “MOLBLOC”, “DEVICE=”, “GASCALS”
Read the next available rate of change of flow.
‘RATE”The next available rate change of flow in the current flow unit of measure persecond is returned.
Command:“RATE”
Reply:“-0.01 sccm/s”
3.4.6.1

See Also

Read the value of Reynolds number representing the current flow through themolbloc as calculated by the molbox1+.
“RE”
The Reynolds number varies with the molbloc flow.
Command:“RE”
Reply:“82.342”
3.4.5

RES(=)
PurposeRead or set the local flow display resolution.

SyntaxRemarks
Example© 2010 Fluke Calibration

Read the progress of or start a purge cycle. Not available on a molbox1+S.
“PURGE=period”“PURGE”
Period:The period of time over which to purge (1.. 999 seconds).
“0” aborts the purge cycle and returns to normal operation.
The purge cycle takes the specified time period to complete. The PURGE
command is used to first start the purge cycle, and then to query how many
seconds are left or if the cycle is complete. While the purge cycle is executing, a‘b’ (“busy”) will appear in the 3rd character position of the “FR” and the “SR”
command replies. The “ABORT” command can also be used to abort a purge
cycle.
The “PURGE” command must be completed or aborted using the “ABORT”
command before performing another operation.
Command:“PURGE=30”
Reply:“30 sec”
Command:“PURGE”
Reply:“12 sec” (purge cycle has 12 sec left)
Reply:“OK” (purge cycle is complete)
ERR# 6:
The argument is invalid.
3.4.4.2 , “SR”; “ABORT”

Syntax“RES=n”“RES”

Default“RES=0.001%”

Argumentsn:Remarks

The molbox1+’s front panel resolution can be specified with this command.
resolution of remote flow measurement replies are always 0.0001% FS.

ExampleSent:
Query reply:“RES=.01”“0.010%”Errors

ERR# 6:

The argument was out of bounds.

See Also

3.4.9

Resolution in %FS (1% - 0.001%)

Page 130

The

4. REMOTE OPERATIONREADYCK(=)
PurposeRead or set a flag that is cleared by a Not Ready condition.
Syntax“READYCK=1”“READYCK”
Defaults“READYCK=1”
Remarks
The internal ready check flag is cleared whenever the molbox1+ reaches a
Not Ready (NR) condition. The "READYCK" command will return the status of thisflag. This flag can be set only by sending the "READYCK=1" command while themolbox1+ is in a Ready (<*>) condition. If you send the "READYCK=1" command whenthe molbox1+ is in a Not Ready (NR) condition, the reply will be "READYCK=0".
If you set READYCK=1 when the molbox1+ achieves a Ready (R) condition, you
can use READYCK later to determine if a Not Ready (NR) condition has occurred.
If NR has occurred, READYCK will return "0". If NR has not occurred, READYCK
will return "1".
ExampleCommand:“READYCK=1” (Set the flag)
Reply:“READYCK=1”
Command:“READYCK”(Query for flag status)
Reply:“READYCK=1” (Has been ready since setting flag)
Errors
ERR# 6:
The argument is not a 1.
See Also
3.1.3, “SR”
REMOTE
Purpose
SyntaxRemarks

ExampleSee Also
RESET
Purpose
SyntaxRemarks

ExampleSee Also
SN
Purpose
SyntaxRemarks

ExampleSee Also

Enable remote local lockout operation.
“REMOTE”
A REMOTE command deactivates the front panel. All front panel controls except [P&T]
will be disabled. The REMOTE command can only be canceled by a LOCAL
command or by turning OFF the molbox1+ power then re-applying it.
Command:“REMOTE”
Reply:“REMOTE”“LOCAL”
Reset the molbox1+ to the default operating parameters.
“RESET”
The RESET command can be given to return certain molbox1+ settings to a default
state. This reset corresponds to the RESET - SETS function from the front panel. The
reset process can take up to 10 seconds to complete, so the user must wait thistime interval before attempting to communicate to the molbox1+ again.
Command:“RESET”
Reply:“RESET”
3.6.1
Read the serial number of the molbox1+.
“SN”
Each molbox1+ is serialized. This serial number is also imprinted on the product labelon the bottom of the molbox1+ and is displayed in the power up introductory
screen.
Command:“SN”
Reply:“SN”
3.6.5.2

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molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

SR
Purpose
SyntaxRemarks

Read the next available ready status.
“SR”
The current Ready/Not Ready status can be read directly using this command. If
the reply is "NR" then the flow is Not Ready within the limits set by the stability
settings, molbloc calibration flow or pressure limits. If the reply is "R" then the flow
is Ready within the limits. The status is replied when the next flow measurement isfinished.
The third character indicates optional additional molbox status information:

ExampleSee Also
SS(%)
Purpose
SyntaxDefaults
Arguments
Remarks

ExampleErrorsSee Also
STDRES(=)
Purpose
SyntaxDefaults
Arguments
Remarks

ExampleSee Also© 2010 Fluke Calibration"r"

molbloc flow is over the maximum Reynolds number of 1 200 allowed fora valid measurement.

“b”

molbox1+ is busy with a tare, leak check or purge cycle which does notallow normal operation.

“a”

molbox1+ is currently executing an averaging cycle.

“P”

molbloc-S BPR is too high or molbloc pressure exceeds molbloc
calibration pressure limits by 10kPa or more (always causes a Not
Ready condition).

“F”

Measured flow exceeds molbloc calibration flow limit by 5% or more(always causes a Not Ready condition).

“SR ”
“R ”
(Flow measurement is ready)“NR ” (Flow measurement is not ready)“R a” (average cycle is executing)“R b” (tare, leak check or purge cycle is executing)“NRP” (BPR is too high for a valid measurement)
3.1.3, “FA”, “FR”, “READYCK”, “SS”, “TARESET”, “PURGE”, “LEAKCK”, “ALLR”
Command:
Reply:
Reply:
Reply:
Reply:

Read or set the flow stability required for a Ready condition to occur (flow unit/s).
“SS=stab”“SS”“SS%=stab%”“SS%”“SS=0.1 sccm”
stab:
The flow stability in flow unit/sec.
stab%:
The flow stability in % FS of the active molbloc.
The stability setting determines whether the flow is ready or not ready. Stability is
set in terms of flow or % FS. It is always stored in terms of flow, so the % FS value
will change if the molbloc range changes. If the rate of change of flow is greaterthan the current setting, then the status is Not Ready.
Command:“SS=.2”
Reply:“0.20 sccm”
Command:“SS%=.1”
Reply:“0.1000 %”ERR# 6:
The argument is invalid.
3.1.3, 3.5.2, “READYCK”, “SR”
Read or set the PRT measurement system auto-calibration reference resistor
values .
“STDRES=R100, R110”“STDRES”“STDRES = 100.0000, 110.0000”
R100:
The actual value of the 100Ω reference resistor.
R110:
The actual value of the 110Ω reference resistor.
These values are stored in the molbox’s factory data area, and should not beroutinely changed due to a limitation of the number of changes allowed (100,000
changes) before the factory data area is subject to failure. Use the channel
dependent “TCAL” command for adjusting the temperature calibration.
Sent:“STDRES=100.002, 109.998”
Reply:“ 100.0020 Ohms, 109.9980 Ohms”
5.4, “TCAL”

Page 132

4. REMOTE OPERATION

TARE
Purpose
SyntaxRemarks

ExampleErrorsSee Also

Read the current tare conditions and the current tare. Not available on amolbox1+S.
“TARE”The user should set the molbox1+ valves to the tare condition (see “TARESETUP”)
and check the tare conditions using this command before taring the internaltransducers (see “TARESET”).
The returned data will allow the user to determine if the current conditions will allow
a valid tare. The reply contains three fields which are separated by commas.
The first field starts with an "R" if the system is ready to tare or else an "NR". The "R"must be present to tare the transducers. The system is ready to tare only if thecurrent difference in pressure [Pa] between the up and down stream RPTs withouttare is below 3,000 Pa. The actual pressure rate of change in Pa/sec follows this text.
The second field displays the current difference in pressure [Pa] between the up anddown stream RPTs without tare. The third field shows the last tare value. All returned
values are in Pascal [Pa]. You cannot be in A+B or A/B modes when taring.
The normal order of remote commands for a tare operation:“TARESETUP=UP” or “TARESETUP=DN” configures the molbox1+ for a tare.
“TARE” queries the molbox1+ for current conditions until it is ready for tare.
“TARESET” tares the molbox1+ when the “TARE” query has shown it is ready.
“TARESETUP=OFF” returns the molbox1+ to normal measurement mode.
Command:“TARE”
Reply:“R 0 Pa/s, 115.2 Pa, 108.1 Pa”
ERR# 6:
An argument is invalid.
ERR# 52:
Cannot tare in A+B or A/B mode.
3.4.4.1, “TARESET”, “TARESETUP”

TARESETUP(=)
PurposeTo prepare the molbox1+ to be tared and to return the unit to normal operation
after a tare has been completed. Not available on a molbox1+S.
Syntax“TARESETUP=mode“TARESETUP”
Defaults“TARESETUP=OFF”“OFF”. Allows normal operation of the molbox1+.
Arguments
mode:“UP”. Connects both of the absolute RPTs to the upstreampressure.
“DN”. Connects both of the absolute RPTs to the downstreampressure.
Before the molbox1+ can be tared, the “TARESETUP” command must be used toRemarks
configure the internal RPT connections properly. After the tare operation is complete,the “TARESETUP” command must again be used to restore the molbox1+ tonormal operation. The “ABORT” command can also return operation to normal.
The normal order of remote commands for a tare operation:“TARESETUP=UP” or “TARESETUP=DN” configures the molbox1+ for a tare.
“TARE” queries the molbox1+ for current conditions until it is ready for tare.
“TARESET” tares the molbox1+ when the “TARE” query has shown it is ready.
“TARESETUP=OFF” returns the molbox1+ to normal measurement mode.
ExampleCommand:“TARESETUP=UP”
Reply:“UP”
Errors
ERR# 6:
An argument is invalid.
ERR# 52:
Cannot tare in A+B or A/B mode.
See Also
3.4.4.1, “TARE”, “TARESET”; “ABORT”

Page 133© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALTARESET(=)
PurposeTo automatically tare the upstream and downstream RPT or set the tare to a user
defined value. Not available on a molbox1+S.
Syntax“TARESET=tare“TARESET”
Defaults“TARESET=0”
Arguments
tare:
The tare value (-9999 to 9999 Pa).
Remarks“TARESET” will automatically tare the molbox1+ only if the tare results are within
the limits given (see the “TARE” command). Use the “TARESETUP” command toprepare the unit to be tared, and the “TARE” command to check if conditions arevalid. After you have completed taring the unit, use the “TARESETUP=OFF”
command or the “ABORT” command to return the unit to normal operating
conditions. You can also manually set the tare value using the “TARESET=tare”
command. All pressure values are always in Pascal [Pa]. While the tare cycle is
executing, a ‘b’ (“busy”) will appear in the third character position of the “FR” and the“SR” command replies.
The normal order of remote commands for a tare operation:“TARESETUP=UP” or “TARESETUP=DN” configures the molbox1+ for a tare.
“TARE” queries the molbox1+ for current conditions until it is ready for tare.
“TARESET” tares the molbox1+ when the “TARE” query has shown it is ready.
“TARESETUP=OFF” returns the molbox1+ to normal measurement mode.
NOTE: This command typically takes 5 to 7 seconds to complete if performing atare (no arguments given).
ExampleCommand:“TARESET”
Reply:“66 Pa”
Reply:“66 Pa, 7 Pa”
Errors
ERR# 6:
An argument is invalid.
ERR# 25:
The tare values exceed the tare limit of 3,000 Pa.
ERR# 52:
Cannot tare in A+B or A/B mode.
See Also
3.4.4.1 , “TARE”, “TARESETUP”, “ABORT”
TCAL(=)
Purpose
SyntaxArguments

Remarks
ExampleErrorsSee Also
TEMP
Purpose
SyntaxRemarks

ExampleErrorsSee Also
TIME(=)
Purpose
SyntaxArguments
ExampleErrorsSee Also© 2010 Fluke Calibration

Read or set the molbox1+ temperature calibration for the active channel“TCAL=adder, mult, date”“TCAL”
adder:
Temperature adder in the current temperature units.
mult:
Temperature multiplier.
date:
Date (YYYYMMDD)
The temperature calibration for active channel is applied to the displayed molbloc
temperature.
Command:“TCAL=0.25, 1.003,20090226”
Reply:“0.250, 1.0030,20090226”
ERR# 2:The date argument is invalid
3.2.2, “TUNIT”, “DEVICE”, “STDRES”

Read the temperature of the active molbloc in the current unit of measure.
“TEMP”The molbloc temperature is returned in the current temperature units. The averagetemperature, upstream temperature and downstream temperature is returned (inthat order). An error will be returned if there is a problem reading the molbloc
PRTs.
Command:“TEMP”
Reply:“17.85 C, 17.84 C, 17.86 C”
ERR# 37:
There is an error in the molbox1+ PRT measurement.
3.2.5, 5.4, 3.4.5 “TUNIT”, “OHMS”, “TCAL”

Read or set the internal clock time.
“TIME”“TIME=hh:mm:m
hh:mmxs:
The time to set in the format where hh is the hours from 1 to 12,
mm is the minutes from 1 to 59 followed by “am” or “pm”.
Command:“TIME=1:22am”
Reply:“01:22am”
ERR# 7:
The time given is invalid.
3.6.5.3

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4. REMOTE OPERATIONTOTAL(=)
Purpose
SyntaxArguments
Remarks

ExampleErrorsSee Also
TUNIT
Purpose
SyntaxArguments
Remarks
ExampleErrorsSee Also
UDU(=)
Purpose
SyntaxArguments

Defaults
ExampleErrorsSee Also
UL(=)
Purpose
SyntaxDefaults
Arguments
Remarks
ExampleErrorsSee Also

Read the progress of or start a new totalize cycle.
“TOTAL=period”“TOTAL”
period:The period to totalize 00:00:01 to 99:59:59 (HH:MM:SS).
“0” stops the totalize cycle before it is complete.
The totalizing cycle accumulates the total mass or volume flowed over a set period,or the user can stop the cycle early if desired to use a shorter period than specified.
The reply to a “TOTAL” query provides the current total, and the elapsed time
period in the HH:MM:SS format. The cycle is complete when the total flow ispreceded by ‘R’ (Ready). If the unit is actively totalizing, an “NR” (Not Ready)proceeds the total flow.
Command:“TOTAL=00:10:00”
Reply:“NR 0.0000 ucc, 00:00:00” (new cycle has started)
Command:“TOTAL”
Reply:”NR 5.2347 ucc, 00:08:21” (cycle has run 8 min, 21 sec)
Reply:”R 6.2634 ucc, 00:10:00” (cycle is complete)
Command:“TOTAL=0”
Reply:”R 5.2347 ucc, 00:08:21” (cycle has completed early)
ERR# 6:
The argument is invalid.
3.4.6.4
Read or set the molbox1+ temperature unit of measure.
“TUNIT=unit”“TUNIT”
unit:‘C’ for Celsius or ‘F’ for Fahrenheit.
The temperature unit is used for reporting the molbloc temperature, and for setting
various other temperature settings.
Command:“TUNIT”
Reply:“C”
ERR# 6:The unit argument is invalid.
3.5.9, “TEMP”
Read or set the user definable pressure unit.
“UDU”“UDU=text, coef”
text:
The text to use to identify the unit. It can be up to four characters wide.
This will be the text used to specify the unit if selecting it remotely,
and that appears on the molbox1+.
coef:
The coefficient to convert Pascal [Pa] to the user unit. The pressure(in Pa) will be multiplied by this coefficient before being displayed.
“UDU=UNIT, 1”
Command:“UDU=Bar2, .00001”
Reply:“Bar2, 0.000010”
ERR# 2:The text argument is longer than four characters.
ERR# 6:The coef argument is invalid.
3.5.8, “PUNIT”
Read or set the upper limit for the internal pressure transducers.
“UL=upperlimit”“UL”“UL=630.00 kPa”
upperlimit:
The upper limit in the current pressure units (0 to 500 kPa).
The upper limit sets the point in which the molbox1+ reacts to protect the internaltransducers; It is in the current pressure units.
Command:“UL=350”
Reply:“350.000 kPa”
ERR# 6:The upperlimit argument is invalid.
3.6.3

Page 135© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALUSERCAL(=)
PurposeRead or set the user flow measurement adjustment.
Syntax“USERCAL=adder, mult”“USERCAL”
Defaults“USERCAL=0, 1”
Arguments
Adder:
The flow adder in the current flow unit and gas type (0 to FS).
Mult:
The flow multiplier (0.1 to 2).
Remarks
The user definable adjustment lets the user modify the measured flow. The adderand multiplier are separated by a comma. The adder is in the current flow unit.
This adjustment will be applied to any molbloc connected to the molbox1+.
ExampleCommand:“USERCAL=.58,.995”
Reply:“0.58 sccm, 0.995000”
Errors
ERR# 6:
The adder or multiplier argument is invalid.
See Also
3.5.3
UTEMP
Purpose
SyntaxDefaults
Arguments
Remarks
ExampleSee Also
VALVE(=)
Purpose
SyntaxArguments
Remarks
ExampleErrorsSee Also
VER
Purpose
SyntaxRemarks
ExampleVLM(=)
Purpose
SyntaxDefaults
Arguments

Remarks
ExampleErrorsSee Also© 2010 Fluke Calibration

Read or set the temperature reference used for the volumetrically based mass flow
unit with user defined reference temperature.
“UTEMP=temp”“UTEMP”“UTEMP=0” (°C)
Temp:
The reference temperature in the current temperature unit ofmeasure.
This temperature reference is used by the user defined units.
Command:“UTEMP=20”
Reply:“20.00 C”
3.4.3.1, 3.4.3.4, “FUNIT”, “TUNIT”
This command is obsolete and should not be used in new designs. The TARESETUP
and PURGE commands should be used instead for special valve operations.
“VALVE=xxx”“VALVE”
xxx:
The driver bitfield.
This command is obsolete.
Command:“VALVE=5”
Reply:“5”
ERR# 6:The xxx argument is not between 0 and 255.
“TARESETUP”, “PURGE”
Read the molbox1+ version.
“VER”
The software version of the molbox1+ can be read. This is useful for checking forthe presence of the molbox1+ and for reference purposes.
Command:“VER”
Reply:“DH INSTRUMENTS, INC molbox1+ Ver5.10 ”
Read or set the volume flow unit of measure pressure temperature conditions.
“VLM=pres(,temp)”“VLM”“VLM=101.325 kPaa, 20°C”
pres:
The user defined pressure in the current pressure unit.
Temp:
The user defined temperature in the current temperature unit. If thisfield is omitted, and just the pressure is given, then the molbloc
temperature will be used as temperature.
The flow volume units "ccm", "lm", "lh", "m3m", "m3h", "cfm" and "cfh" requirepressure and a temperature conditions to be specified by the user.
Command:“VLM=200”
Reply:“200.00 kPaa” (molbloc temp will be used)
Command:“VLM=200, 15”
Reply:“200.00 kPaa, 15°C” (user defined temp will be used)
ERR# 6:
One of the arguments is invalid.
3.4.3.1, 3.4.3.4 “FUNIT”

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4. REMOTE OPERATION

VIN
Purpose
SyntaxRemarks

ExampleErrorsSee Also
VOUT(=)
Purpose
SyntaxDefaults
Arguments
Remarks

ExampleErrorsSee Also
VSENSE
Purpose
SyntaxRemarks

ExampleErrorsSee Also
VSUPPLY
Purpose
SyntaxRemarks
ExampleRead the MFC measurement voltage if in voltage mode.
“VIN”
The optional MFC interface can measure voltage sent from an MFC. The
molbox1+ must be in voltage mode before this can be done. The returned data isalways in “v”.
Command:“VIN”
Reply:“1.982 V”
3.4.8, 7.3, “MFCCH”, “VOUT(=)”
Send a voltage to the MFC if in voltage mode.
“VOUT=voltage”“VOUT”“VOUT=0”
voltage:
The voltage to be sent to the MFC (0 to 5.5 V).
The optional MFC interface can set a voltage sent to an MFC. The molbox1+ must
be in voltage mode before this can be done (see the “MFCCH” command). The datais always in Volts. This command does not change the regulation target set point
for the MFC.
Command:“VOUT=3”
Reply:“3.000 V”
ERR# 6:
The Volts argument is invalid.
ERR# 10:The MFC option is not installed or is not enabled.
ERR# 15:
The molbox1+ is not in current mode.
3.4.8, 7.3, “MFCCH”, “VIN”
Read the voltage sensed at the DUT set terminal.
“VSENSE”
The optional MFC interface uses a voltage sense line to measure the voltage being
sent to an external MFC at the MFC. This sense voltage is used to re-adjust thevoltage sent to the MFC to compensate for line losses.
Command:“VSENSE”
Reply:“3.002 V”
3.4.8, 7.3, “MFCCH”, “VIN”, “VOUT”
Read the current ±15 Volt MFC supply voltage.
“VSUPPLY”
The optional MFC interface provides a ±15 Volt supply. These two measurements
are referenced to the MFC supply common, and are sensed in the molbox1+.
Command:“VSUPPLY”
Reply:“+14.982 V, -15.231 V”

See Also
VVALTEST
Purpose
SyntaxRemarks
ExampleSee Also

3.4.8, 7.3, “MFCCH”, “VIN”, “VOUT”
Read the voltage at the optional MFC interface valve test input.
“VVALTEST”
The optional MFC interface provides an input to measure the MFC valve test voltage.
This measurement is referenced to the MFC -15 Volt supply.
Command:“VVALTEST”
Reply:“5.32 V”
3.4.8, 7.3, “MFCCH”, “VIN”, “VOUT”

Page 137© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUALZOFFSET:HI(=) and ZOFFSET:LO(=)
PurposeRead or set the AutoZ pressure offset (Poffset) for the high (“HI”) or low (“LO”) RPT .
“ZOFFSET:HI =offset”
Command:“ZOFFSET:LO =offset”“ZOFFSET:HI”
Query:“ZOFFSET:LO”
Defaults“ZOFFSET:HI = 0.0”
“ZOFFSET:LO = 0.0”
Arguments
offset:
The RPT pressure offset (“Poffset”) in Pa.
Remarks
The pressure offset (Poffset) for the specified RPT (HI or Lo) can be accessed withthis command. Using this program message overwrites the current offset, so caution
must be used. Changes made using this program message take effect immediately.
ExampleSent:“ZOFFSET:LO=2.1”
Reply:“ 2.10 Pa”
Errors
ERR# 6:
One of the arguments is out of range.
See Also
3.4.4.4, “AUTOZERO” command

4.4

Status System

The status system includes the status reporting system which reports general molbox1+ events. The
user can select which molbox1+ events will cause a status change event. These events are thenreported to the status system (bit7 and bit3 of the status byte register), which also must be configured for
the STATus subsystem to generate the service requests described in Section 4.4.1, Status Reporting
System.
There are two 16 bit event registers that make up the top layer of the status subsystem. The OPERation
status register handles conditions that are normal for the molbox1+. The QUEStionable status register
handles events that could cause measurements to be made under questionable conditions.
Other registers layered below these two registers provide the structure necessary to handle the two RPT
channels and to enable the events and event transitions. Bit15 of all of these registers is not usedbecause bit15 represents a sign bit on some computer systems.

4.4.1

Status Reporting System

The molbox1+ status reporting system is used to track and report system status and errors.
The status subsystem is layered under and reports to the status reporting system. It follows
the model of the IEEE Std 488.2 and works for the COM1 and the IEEE-488 port with slight differences.
The molbox1+ can be programmed to respond to various status conditions by asserting the
SRQ of the IEEE-488 interface. The COM1 port cannot be supported in this manner, so pollingmust be used.

4.4.1.1

Status Byte Register

The molbox1+ contains an 8 bit status byte register that reflects the general
status of the molbox1+.
Table 40. Status Byte Register
OPER
(128)

RQS/MSS
(64)

ESB
(32)

MAV
(16)

N/A
(8)

ERROR
(4)

N/A
(2)

RSR
(1)

This register is affected by the molbox1+ reply output queue, the error queue, theStandard Event Status register, the Ready Event Status register and the
STATus subsystem.

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4. REMOTE OPERATION

Status Byte Register(“∗STB?” or ”∗SRE n”)
OPER←←←
Bit7 (128)
RQS/MSS
Bit6 (64)ESB
Bit5 (32)
MAV
Bit4 (16)N/A
Bit3 (8)ERROR
Bit2 (4)N/A
Bit1 (2)N/A
Bit0 (1)

←←←
←←←

←←←

OPERation summary bitStandard Event Status Register(“∗ESR?” or “∗ESE n”)
PON
URQ
CMD
EXE
DDE
QYE
Bit7
Bit6
Bit5
Bit4
Bit3
Bit2
OUTPUT
QUEUE

RQC
Bit1

OPC
Bit0

ERROR
QUEUE

Figure 14. Status Byte Register

The status byte register can be read using the “*STB?” query, or by performing a
serial poll on the IEEE-488 bus. If you read this using a serial poll then bit 6 isthe RQS. If the “∗STB?” query is used, then bit 6 is the MSS bit. All of the otherbits are common to both types of query.
Each of these status bits can cause a SRQ to occur. The Service Request
Enable Register (“∗SRE” program message ) determines which of these flags areable to assert the SRQ line. This enable register has a matching set of bits that eachwill enable the designated bit to cause a SRQ, except for the RQS/MSS bit(s)which cannot cause a SRQ. If you set this register to 20 ($14 hex), an SRQ will occur
if the MAV or the ERROR bit are set. The description of these bits are given as:•

OPER: OPERational event register summary bit (Bit 7)
This bit is not supported by the molbox1+.

•

RQS: Requested Service (Bit 6)
Indicates that the SRQ line of the IEEE-488 interface has been asserted by
the molbox1+. This bit is cleared when a serial poll is performed on themolbox1+, and is a part of the status byte register when read using a serial
poll. This bit does not apply if the COM1 port is being used.

•

MSS: Master Summary Status (Bit 6)
Indicates that an event or events occurred that caused the molbox1+ torequest service from the Host, much like the RQS bit. Unlike the RQS bit, it
is READ ONLY and can be only cleared when the event(s) that caused theservice request are cleared.

•

ESB: Event Summary Bit (Bit 5)
Indicates if an enabled bit in the Standard Event Status Register became set.
(See Section 4.4.1.2.)•

MAV: Message Available Bit (Bit 4)
Indicates that at least one reply message is waiting in the molbox1+ IEEE488 output queue.

•

ERR: Error Queue not empty (Bit 2)
Indicates that at least one command error message is waiting in themolbox1+ IEEE-488 error message queue. Use the “SYSTem:ERRor?”query to get this message.

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4.4.1.2

Standard Event Register

The molbox1+ contains an 8 bit Standard event register that reflects specificmolbox1+ events that are not RPT dependent. Enabled events in this register
will set or clear the ESB bit of the status byte register.
Table 41. Standard Event Register
PON
(128)

URQ
(64)

CMD
(32)

EXE
(16)

DDE
(8)

QYE
(4)

RQC
(2)

OPC
(1)

This register can be read using the “*ESR?” query. Each of these status bits can set
the ESB bit of the status byte register, causing a SRQ to occur IF the ESB bit isenabled to do so. The Standard Event Status Enable Register (“∗ESE” program message)
determines which of these flags are able to assert the ESB bit. The descriptionof these bits are given as:© 2010 Fluke Calibration•

PON: Power On (Bit 7)
Indicates that the molbox1+ power has been cycled since the last time thisbit was read or cleared.

•

URQ: User Request (Bit 6)
Indicates that the molbox1+ was set to local operation manually from thefront panel by the user (pressing the ESC key).

•

CMD: Command Error (Bit 5)
Indicates that a remote command error has occurred. A command error istypically a syntax error in the use of a correct program message.

•

EXE: Execution Error (Bit 4)
Indicates if a remote program message cannot be processed due to device
related condition.

•

DDE: Device Dependent Error (Bit 3)
Indicates that an internal error has occurred in the molbox1+ (e.g., a transducer
time-out).

•

QYE: Query Error (Bit 2)
Indicates that an error has occurred in the protocol for program message
communications. This is typically caused by a program message being sent
to the molbox1+ without reading a waiting reply.

•

RQC: Request Control (Bit 1)
This bit is not supported as the molbox1+ cannot become the active
controller in charge.

•

OPC: Operation Complete (Bit 0)
Indicates that the molbox1+ has completed all requested functions.

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5.

Maintenance, Adjustments andCalibration

5.1

Product Overview

molbox1+ was designed for maintenance free operation. No maintenance is required other than:•

Taring of Reference Pressure Transducers (RPTs) to zero differential for molbloc-L operation:
This function is not a separate MAINTENANCE function or automatic molbox1+ activity, it is part ofregular operation (see Section 3.4.4.1).

•

AutoZero of Reference Pressure Transducers (RPTs): Regular rezeroing of the RPTs absolutemeasurement mode to a barometric reference standard using the AutoZ function is recommended(see Section 3.4.4.4).

•

Reference Pressures Transducer (RPT) Calibration: An annual recalibration cycle is recommended.
See Section 5.2 for RPT calibration instructions.

•

Optional MFC Control Function Verification: The stability of the MFC control function analog
voltage and current measurements over time is dependent upon the conditions of use. The MFC control
function accuracy should be verified regularly. See Section 5.3 for instructions.

•

Ohmic Measurement System Verification: A five year verification interval is recommended. See
Section 5.4 for instructions.

•molbloc Calibration: molblocs can be calibrated separately from the molbox1+. A one year recalibration
cycle is recommended. Calibration of a molbloc consists of comparing the mass flow measured by
the combination of the molbloc and a calibrated molbox to a suitable mass flow standard flowing thegas for which the calibration is being performed. Since the molbloc is a static, stainless steel element,characterized by proprietary calibration coefficients determined in the original factory calibration, an out of
tolerance molbloc is usually considered to require repair. For facilities requiring the capability toadjust molblocs to agree with their mass flow standard, CalTool for molbloc Extension to
COMPASS for Flow software is available.

This section provides information on maintenance, adjustment, calibration procedures and recommended
overhaul procedures.

Note
Calibration, maintenance and repair services for molbox1+ are offered by Fluke
Calibration Authorized Service Providers (see Section 7.4).

 Caution•

molbox1+ is a sophisticated measuring instrument with advanced on-board
features and functions. Before assuming that unexpected behavior is caused
by a system defect or breakdown, use this manual and other training facilities
to become thoroughly familiar with molbox1+ operation. For rapid assistancein specific situations and other troubleshooting information, see Section 6.

•

molbox1+ is covered by a limited 1 year warranty (see Section 7.4).
Unauthorized service or repair during the warranty period is undertaken at theowner's risk and may cause damage that is NOT covered under productwarranty and/or may void the product warranty.
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5.2

Calibration Of Reference Pressure Transducers(RPTS)
5.2.1

Principle

molbox1+ has two nominally identical, absolute Reference Pressure Transducers (RPTs)
used to measure molbloc upstream and downstream pressure.
To calibrate an RPT, pressure from a pressure standard is applied to the RPTs at ascending
and descending pressure increments over the RPT range. The pressure defined by thestandard and the corresponding RPT readings are recorded at each point. After all of thepressures have been applied and recorded, adjustments are made to fit the RPT pressure
readings to the standard. Fitting the readings means performing a least squares linear
regression to arrive at the lowest value of the residual of errors of the transducer relative tothe standard. The transducer readings are adjusted by user settable coefficients: PA (a pressureadder or offset) and PM (a pressure multiplier or span set) (see Section 5.2.1.1).
molbox1+ is delivered with an interactive reference pressure transducer (RPT) calibration
utility software program that steps the operator through the complete RPT calibration
procedure including applying pressures, collecting data automatically, calculating new PA
and PM values, previewing the results of the new calibration and activating the results of the
new calibration (see the CalTool for RPTs program and documentation provided on the
General Accessories disk delivered with molbox1+). molbox1+ also provides complete local
and remote access to RPT calibration coefficients so that RPT calibrations can be performed
without using CalTool software if desired (see Section 5.2.5).

 Caution
CalTool for RPTs software provided with the molbox1+ supports thecalibration process of molbox1+ RPTs. The CalTool program and its
manual are provided on the General Accessories Disk with the newmolbox1+. Most users should use CalTool software to assist in thecalibration of molbox1+ RPTs.

5.2.1.1

PA and PM Coefficients

The coefficients used to adjust RPT readings are designated PA (a pressureadder or offset) and PM (a pressure multiplier or span set). The coefficientsaffect the RPT reading following:
Corrected reading = (uncorrected reading • PM) + PA
PA is expressed in pressure (always the SI unit, Pascal [Pa]).
PM is dimensionless.
There are individual PA and PM values for each of molbox1+’s two RPTs. The PA and PM
values currently in use for each RPT can be viewed in the CALIBRATION function or
the “PCAL” remote command. If adjustments are necessary when calibrating an
RPT, the adjustments are made by adjusting the PA and PM values.

 Caution
As editing PA and PM values will change RPT calibration, theyshould only be edited by qualified personnel as part of thecalibration process. Caution should be taken to avoid accidental
editing. For information on preventing access to calibration
information, see Section 3.6.2.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONNote
A new molbox1+ is delivered with all PA and PM values set to zeroand 1. This does NOT mean that the molbox1+ has NOT beencalibrated.
For the original factory calibration, privileged
factory coefficients are used for calibration adjustment. This
allows a new molbox1+ to be delivered with “virgin” calibration
coefficients of PA = 0 and PM = 1.

5.2.2

Equipment Required

To calibrate molbox1+’s absolute reference pressure transducers (RPTs) to factory
specifications, a gas operated pressure standard with the following characteristics
are required:•

Able to apply absolute pressure in increments between:•

20 to 300 kPa (3 to 45 psia) for molbox1+ A350K;•

20 to 600 kPa (3 to 87 psia) for molbox1+ A700K;•

100 to 1400 kPa (14 to 203 psia) for molbox1+S A1.4M;•

100 to 2000 kPa (14 to 290 psia) for molbox1+S A2M;•

It is NOT necessary that the reference pressure standard used apply precisely thenominal pressure value of the calibration points as long as the exact value of the appliedpressure is known. A different pressure range may be used if it is known that themolbox1+ will not be used outside of the different range.

•

Measurement uncertainty (accuracy) of ± 0.005 % of reading or better, if normal
molbox1+ flow measurement uncertainty specifications are to be obtained. A standard
with higher measurement uncertainty may be used but molbox1+ flow measurement
uncertainty may be proportionally degraded from published specifications.

 Caution
Use only a clean dry gas source when calibrating molbox1+ RPTs.
Contaminating molbox1+ with liquids can cause out of tolerance
measurements and may require special factory cleaning.

Note
DHI piston gauge Model PG7601 is recommended as the reference
pressure standard for the calibration of molbox1+ RPTs. Contact Fluke
Calibration or your local representative for additional information.

5.2.3

Set-Up and Preparation

To set-up and prepare the molbox1+ for calibration:
 Set the molbox1+ on a stable surface near the calibration standard at a height as close
as possible to the calibration standard's reference height. Consider the connections thatneed to be made to the molbox1+ rear panel pressure quick connectors and access tothe front panel display and keypad.
 Connect the calibration standard’s output to the molbox1+ rear panel CHANNEL A UP
(HI) and DOWN (LO) ports. In <run> calibration mode (see Section 5.2.4.1), with amolbox1+ both absolute RPTs are connected to the CHANNEL A UP (HI) port and isolated
from the DOWN (LO) port, but for a molbox1+S the absolute RPTs are independently
connected to the CHANNEL A UP (HI) port and the CHANNEL A DOWN (LO) port. Use thequick connector stems (DHI P/N 3068652, equivalent to Swagelok SS-QM2-S-200)
supplied with the molbox1+ accessories to make the connection(s). The fitting on thequick connector stem that must be mated to is a compression type for 1/8 in. tube.
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5.2.4

Viewing and Editing RPT Readings and Calibration
Information
 Caution
Editing RPT calibration information will affect molbox1+ pressure
measurements and can cause out of tolerance flow measurements. RPT
calibration information should only be edited by qualified personnel aspart of the calibration process. Caution should be taken to avoid
accidental editing. For information on preventing access to calibration
information see Section 3.6.2.

 PURPOSE
To read the output of molbox1+ RPTs in calibration mode; view and edit the calibration
coefficients and calibration date.
 PRINCIPLE
The molbox1+ CAL function contains all of the functions needed to perform RPT calibrations
in one menu area.
This includes:•

Viewing molbox1+ RPT outputs (pressure readings) directly without the tare (see Section
3.4.4.1) or head (see Section 3.6.8) applied and configured for application of calibrationpressures to run the calibration.

•

Viewing PA and PM calibration coefficients and the calibration date (see Section 5.2.1.1).

•

Editing PA and PM calibration coefficients and the calibration date (see Section 5.2.1.1).

Note
See Sections 5.2.1 and 5.2.1.1 for information on molbox1+ calibration
coefficients (PA and PM) and their proper use.

5.2.4.1
Viewing RPT outputs

OPERATION

To view the molbox1+ RPT outputs press[SPECIAL], <4cal>, <1pres>, <1upstrm or
2downstrm>, <1run>.
molbox1+’s internalvalves operate to connect both absolute RPTs
to the upstream (HI) pressure port (see Figure14) and the display is:

upstrm RPT
97.830 kPaa

dwnstrm
97.825The upstream absolute RPT reading is on the left and the downstream absolute
reading is on the right. The values displayed are the RPT readings with thecurrent PA and PM calibration coefficients applied but WITHOUT the tare orhead applied (see Sections 3.4.4.1 and 3.6.8). Both the upstream anddownstream absolute RPTs are shown together because they are nominallyidentical and are normally calibrated simultaneously.
Pressing [ESCAPE] or [ENTER] returns to the previous screen.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONNote
The RPT readings viewed under [SPECIAL], <4cal> DO NOT havethe tare (see Section 3.4.4.1) or a head (see Section 3.6.8)
correction applied and are valid for RPT calibrations. The RPT
readings viewed by pressing [P&T] DO have tare and head values
applied and therefore should NOT be used for taking RPT
calibration data (see Section 3.4.4.1 for information on tare values).

1. Channel A High Isolation: Open
2. Channel A Low Isolation: Closed
3. Channel B High Isolation: Closed
4. Channel B Low Isolation: Closed
5. Bypass: OpenFigure 15. molbox1+ Internal Pneumatic Schematic RUN UPSTREAM OR DOWNSTREAM ABSOLUTE RPT CALIBRATION

5.2.4.2
Viewing and Editing RPT PA, PM and Calibration
Date

PURPOSETo view or edit PA and PM calibration coefficients (see Section 5.2.1.1) and thecalibration date for each Reference Pressure Transducer (RPT).

Note
Capability to view and edit the values of the reference resistors
used by molbox1+’s ohmic measurement system (see Section 5.4)
is also provided here. This capability is normally used only by a
Fluke Calibration Authorized Service Provider.

 Caution
Editing RPT, MFC and/or reference resistor calibration
information will affect molbox1+ pressure and/or temperature
measurements
and
can
cause
out-of-toleranceflow
measurements. Calibration information should only be edited
by qualified personnel as part of the calibration process.
Caution should be taken to avoid accidental editing. For
information on preventing access to calibration information see
Section 3.6.2).


OPERATION

Press [SPECIAL], <4cal>, <1pres> and then <1upstrm> or <2dnstrm> tospecify the RPT to be viewed/edited. Finally select <2view> to view information
only or <3edit> to make changes to calibration information.
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1.

Current adder (always in Pascal [Pa]). This isan edit field if <3edit> was selected.

2.

Indication of which RPT calibration information
is being viewed/edited.

3.

This is an Current multiplier (dimensionless).
This is an edit field if <3edit> was selected.

PA:
PM:

0.0 dnstrm RPT
1.00000

If <3edit> was selected, edit the values of PA and PM as desired.
Pressing [ESCAPE] returns to the <1run 2view 3edit> screen without
making changes. Press [ENTER] to continue.
The display is:1.

Current calibration date in YYYYMMDD
format for the selected RPT. This is an edit
field if <3edit> was selected. The default dateis 19800101..

dnstrm RPT cal date:
19990214

If <3edit> was selected, edit the calibration date as desired using a
YYYYMMDD format. Pressing [ESCAPE] returns to the <1run 2view 3edit>
screen without making changes. Press [ENTER] to continue. If <3edit> wasselected and changes have been made to PA, PM or the calibration date, aconfirmation screen is presented to <Activate changes>. Pressing [ESCAPE]
or selecting <1no> returns to the <1run 2view 3edit> screen without
making changes. Selecting <2yes> activates changes and returns to the <1run
2view 3edit> screen.

Note

5.2.5

•

There is a specific calibration date for each RPT. Changing
the calibration date of one RPT does not change the other.

•

The value of PA is always in Pascal [Pa]. The value of PA
must be entered in the pressure unit Pascal [Pa]. If yourcalibration data is in a unit other than Pascal, the calculated
value of PA will be in the other unit and must be converted to
Pascal before it is entered (see Section 7.1.1 for pressure
unit conversions). The value of PM is dimensionless.

RPT Calibration/Adjustment Procedure Without Using
CalTool for RPTs Software Caution
Most users should use CalTool for RPTs software to assist in thecalibration of molbox1+ reference pressure transducers. CalTool for RPTs
and its documentation are provided on the General Accessories Disk
delivered with molbox1+.
Whether using CalTool or not, before
proceeding to calibrate molbox1+ RPTs, Sections 5.2.1 through 5.2.4 ofthis manual should be reviewed thoroughly.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION

Both molbox1+ RPTs are normally calibrated simultaneously.
procedure is:

The standard calibration

 Set-up and prepare the molbox1+ for calibration of the RPT(s) (see Sections 5.2.2,
5.2.3).
 Press [SPECIAL], <4cal>, <1pres>, <1upstrm>, <2view> to read and record the current
values of PA and PM for the upstream RPT. Then repeat the process selecting<2dnstrm> to read and record the downstream RPT PA and PM (see Section 5.2.4.2).
 Press [SPECIAL], <4cal>, <1pres>, <1upstrm> or <2dnstrm>, <1run> to display thereal time pressure readings of the RPT(s) to be calibrated (see Section 5.2.4.1).
 Apply the calibration pressures to the RPT(s) recording the pressure applied by thestandard and the molbox1+ RPT readings at each calibration point.
 See the beginning of section 5.2.2 for the standard calibration range for the RPTs. Dwellat least 60 seconds after setting the reference pressure at each point to allow
full stabilization. The data recorded is the "as received" data for this calibration.
 Enter the calibration pressure and RPT readings for each point into a spreadsheet.
Calculate the "non-corrected" RPT readings by backing out the as received PA and PM
recorded in Step  above, following:
non-corrected reading = (corrected reading - PA)/PM Perform a best fit linear regression to find the offset and slope that best fit the noncorrected RPT readings to the calibration standard pressures. Most commercial
spreadsheet products have a standard function to perform a linear regression.
The offset, in Pascal [Pa], is the new value of PA, the slope is the new value of PM.
 Press [SPECIAL], <4cal>, <1pres>, <1upstrm> or <2dnstrm>, <2edit> to write the newvalues of PA (always in Pascal) and PM and the new calibration date (YYYYMMDD) for
the RPT that is being calibrated.
 Calculate “as left data" for the calibration:
as left reading = (non-corrected reading • new PM) + new PA If desired, verify the as left data by rerunning the calibration with the new PA(s) andPM(s) applied and checking that the disagreements between the calibration standard andthe RPT readings are in tolerance.

 Caution•

The value of PA must be entered in the pressure unit Pascal [Pa]. If thecalibration data is in a unit other than Pascal, the calculated value of PA
will be in the other unit and must be converted to Pascal before it isentered (see Section 7.1.1 for pressure unit conversions).

•

If you are not familiar or comfortable with the mathematics used for PA
and PM manipulation, it is recommended you verify the as left readings assuggested in Step  above to provide practical confirmation of theintegrity of the calculations. Note also that the CalTool for RPTs softwaredelivered with the molbox1+ performs the necessary calculations
automatically.

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5.3

MFC Control Function Adjustment

 PURPOSE
To verify and adjust the voltage and/or current measurements made by molbox1+’s optional MFC control
function.

Note
Capability to view and edit the values of the voltage references resistors used bymolbox1+’s optional MFC control function is also provided here. This capability isnormally used only by a Fluke Calibration Authorized Service Provider.
 PRINCIPLE
molbox1+ may be delivered with an optional MFC control function. The MFC control function allows
voltage of current set points to be applied to an MFC and voltage or current values to be read back froman MFC or MFM.
The MFC control function is self-calibrating using on-board 5 and 10 V references. Voltage is converted
to current using a precision 250 Ω resistor.
The MFC control function signals are:•sense (V)•measure (V or mA)•

valve (V)•negative power supply (V)•positive power supply (V)•set (V or mA)

See Section 1.2.4 for complete MFC control specifications.
Any of the MFC control signals can be adjusted using adders and multipliers in the same manner as thepressure adders and multipliers used to adjust the molbox1+ RPTs (see Section 5.2.1.1). The normal
procedure, however, is to use the molbox1+ Analog Calibration software and cable provided with theaccessories of a molbox1+ delivered with the optional MFC control function.
See Section 7.3 for MFC control function pin out details.
 OPERATION

Note
This section describes the operation of the features available to adjust the optional
molbox1+ MFC control function signals. The normal procedure for calibrating or
adjusting these signals is to use the molbox1+ Analog Calibration software provide
in the molbox1+ accessories. The features described here are made available foradvanced users desiring to perform customized adjustments.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATION

To access the MFC control function signal adders and multipliers pressure [SPECIAL], <4cal>, <3MFC>,<1cal>. The display is:
Channel1:1sense 2meas
To access the MFC control function signal adders and multipliers
pressure [SPECIAL], <4cal>, <3MFC>, <1cal>. The display is:

3valve 4neg 5pos
6set↓

Each selection displays the signal adder and multiplier. For certain signals, <1voltage> or <2current>
must be selected. In this case, there are separate and distinct adders and multipliers for voltage andcurrent readings.
<1sense>:Set point sense. Voltage only.

<2meas>:

Output from the MFC or MFM sensor. Voltage or current.

<3valve>:

Valve test line to measure an MFC valve’s internal voltage. Voltage only.

<4neg>:-15 VDC power supply. Voltage only.

<5pos>:+15 VDC power supply. Voltage only.

<6set>:

MFC set point command. Voltage or current.

5.4


OHMIC Measurement [Temperature] System
Verification
PURPOSETo verify the measurements made by molbox1+’s ohmic measurement system for temperature.


PRINCIPLE

molbox1+ includes an ohmic measurement system used to measure the resistance of the two Platinum
Resistance Thermometers (PRTs) mounted in molblocs. The temperature of the PRTs is calculated fromthe resistance. The molbloc PRTs have nominal resistance at 0 °C of 100 Ω and a slope of 0.3896
following DIN Norm 43760. The calibrated Rzero corresponding to the resistance at 0 °C for each PRT is
stored on the molbloc EEPROM and read by the molbox1+.
The ohmic measurement system self-calibrates using on-board 100 and 110 Ω reference resistors.
On molbox1+ power up, an automated routine adjusts the ohmic measurement system relative to on-board,reference resistor readings. The on-board reference resistors used to calibrate the molbox1+
measurement system have accuracy of ± 0.01 % and stability of ± 0.0025 % for one year, ± 0.005 % forthree years.
The self-calibration feature and the very high accuracy and stability of the reference resistors relative tothe accuracy tolerance on the molbox1+ temperature measurements make the need to calibrate theohmic measurement system independently unlikely. It is good practice, however, to verify the ohmic
measurement system. This is most easily accomplished globally by connecting a known resistance value
to the measurement circuit where the molbloc PRTs are normally connected and verifying that themolbox1+ reads the correct corresponding temperature when that resistance is connected. Reference
resistors mounted in a molbloc simulator for easy connection to molbox1+ using the normal molbloc
connection cable can be purchased from your Fluke Calibration Sales Representative [molbloc
simulators: 100 Ω (0°C nominal) P/N 3069694, 107 Ω (18°C nominal) P/N 3069682, 110 Ω (25°C
nominal) P/N 3069701)]. These are nominal resistors whose values are reported and can be measured
independently if desired. The measured resistance of the reference resistors and a value for resistance at 0
°C of 100 Ω are programmed on the simulator EEPROM. Using these values, if the molbox1+ ohmic
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measurement system and associated connections are working properly, when the simulator is connected
the molbloc temperature indicated by molbox1+ should equal the reference temperature corresponding to themolbloc simulator reference resistors Rzero values following:
Reference temperature [°C] = (Reference resistor value [Ω] – 100) / 0.3896
The Reference temperature [°C] calculated from the actual reference resistor value is written on themolbloc simulator. The temperature value read by the molbox1+ when the molbloc simulator isconnected can be observed by pressing [P&T] (see Section 3.4.5). The disagreement between thereference temperature and the molbloc indication should not exceed 0.05 °C.

Note
Because the ohmic measurement system is set up to measure two PRTs, there are
two reference resistors in the molbloc simulator. Their resistance is not identicalso there are actually two reference temperatures printed on the molbloc simulator
and an average temperature which correspond to the three temperatures on themolbox1+ [P&T] temperature display (see Section 3.4.5).


OPERATION

To verify the molbox1+ ohmic measurement system proceed as follows: Connect a molbloc simulator to the molbox1+ Channel A and initialize it as if connecting a molbloc(see Section 3.5.1).
 Press the [P&T] button twice to display the molbox1+ temperature measurement.
 Compare the three molbox1+ temperature measurements (upstream, downstream and average) tothe calculated reference temperature values written on the molbloc simulator.
 Repeat steps  thru  for the other simulators and/or for Channel B.


If all disagreements between molbox1+ indications and corresponding calculated reference
temperatures are less than 0.05 °C, the ohmic measurement system verification passed.
If any disagreement between a molbox1+ indication and the corresponding calculated reference
temperature is greater than 0.05 °C, the ohmic measurement system verification failed.

Possible reasons for failure include:•

faulty molbox1+ internal reference resistor(s)•faulty molbox1+ internal relays•

faulty connections between molbox1+ and the molbloc simulator•

faulty molbloc simulator

Check the molbox1+ to molbloc simulator connections and repeat the verification.

 Caution
Pressing [SPECIAL] and selecting <4cal>, <2temp> provides access to view andedit the value of molbox1+’s channel dependent temperature adders andmultipliers. Altering these values can cause out of tolerance flow readings. In
normal circumstances, these values are only altered by the factory when areference resistor is replaced and great care and consideration should be used ifthey are to be altered by the user.

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5.4.1

OHMIC Measurement System Calibration/Adjustment
Procedure

The molbox1+ channels are calibrated individually. The standard calibration procedurerequires at least two simulators and is performed as follows: With Channel A selected, press [SPECIAL], <4cal>, <2temp> to read and record thecurrent values of TA and TM for Channel A, then exit to the main run screen to selectChannel B and repeat the process to read and record the current values of TA and TM
for Channel B.
 With Channel A selected, the [P&T] button twice to display the real time temperature
readings.
 Connect a molbloc simulator to the molbox1+ Channel A and initialize it as if connecting amolbloc (see Section 3.5.1).
 Enter the average molbloc simulator calibrated temperature and the molbox1+ top row
centered calibration temperature reading (the averaged temperature) for eachtemperature point into a spreadsheet. Repeat steps  and  for each simulator.
Calculate the "non-corrected" temperature readings by backing out the as received TA
and TM recorded in Step  above, following:
non-corrected reading = (corrected reading - TA)/TM

Perform a best fit linear regression to find the offset and slope that best fit the noncorrected temperature readings to the calibrated molbloc simulator temperatures. Most
commercial spreadsheet products have a standard function to perform a linear
regression. The offset, in the current temperature unit, is the new value of TA, the slope
is the new value of TM.

 Press [SPECIAL], <4cal>, <2temp> to write the new values of TA (in the current unit ofmeasure) and TM and the new calibration date (YYYYMMDD) for the channel that isbeing calibrated.
 Calculate “as left data" for the calibration:
as left reading = (non-corrected reading • new TM) + new TA If desired, verify the as left data by rerunning the calibration with the new TA and TM
applied and checking that the disagreements between the molbloc simulators and themolbox1+ temperature readings are in tolerance.
 Repeat steps  thru  for Channel B.

 Caution•

The value of TA must be entered in the current unit of measure, either °C
or °F, that is displayed by the molbox1+.

•

If you are not familiar or comfortable with the mathematics used for TA
and TM manipulation, it is recommended you verify the as left readings assuggested in Step  above to provide practical confirmation of theintegrity of the calculations.

•

If an out-of-tolerance condition persists, the molbox1+ and/or the molbloc
simulator(s) may need service.

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5.5

molbloc Flow Adjustment

 PURPOSE
To allow linear adjustments to existing gas specific molbloc calibrations by the user.

 Caution•

This correction does not take into consideration changes in the molbloc
Reynolds number. It is a pure adder/multiplier applied to the molbloc flow.
For a molbloc-L a variety of upstream and downstream pressure andtemperature combinations may yield the same Reynolds number. It is
important to calibrate the molbloc in the conditions of normal use to avoid
inducing additional error associated with changes in the Reynolds number.

•

For true factory style gas calibrations or addition of gas calibrations notpreviously on the molbloc, the use of the CalTool for molbloc Extension to
COMPASS for Flow is highly preferable if access to a sufficiently accurate
flow reference is available.

 PRINCIPLE
The adjustments are stored on the molbloc EEPROM along with the factory calibration coefficients anddoes not apply to any other molbloc or gas calibration. The correction is applied whenever the specificgas calibration is selected on the adjusted molbloc when connected to a molbox1+. This feature does notsupport adding new calibrations to the molbloc.
The coefficients used to adjust the gas calibration are designated FA (a flow adder or offset) and FM (aflow multiplier or span set). The use of FA is not recommened as this is an offset value (% of FS) that
could negatively impact the molbloc, which is a % of reading device. Whenever possible it isrecommended to make all corrections with the FM. The coefficients affect the flow reading following:
Corrected reading = (uncorrected reading • FM) + FA
FA is expressed in flow (always the current unit of measure (i.e. “sccm” or “slm”).
FM is dimensionless.
The FA and FM values currently in use for the calibrated gas can be viewed in the CALIBRATION function.
If adjustments are necessary when calibrating a molbloc, the adjustments are made by adjusting the FA andFM values.

 Caution
As editing FA and FM values will change the molbloc gas calibration, they should
only be edited by qualified personnel as part of a flow calibration process. Caution
should be taken to avoid accidental editing. For information on preventing accessto calibration information, see Section 3.6.2.

Note
A new molbloc is delivered with all FA and FM values set to zero and 1. This does
NOT mean that the molbloc has NOT been calibrated. For the original factory
calibration, privileged factory coefficients are used for calibration adjustment.
This allows a new molbloc to be delivered with “virgin” calibration coefficients of
FA = 0 and FM = 1.

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5.5.1

molbloc Adjustment Procedure Without Using
CalTool for molbloc Software

The standard calibration procedure is: Set-up and prepare the molbloc for calibration of the flow by connecting it to a flow
reference with the gas to be tested.
 Press [SPECIAL], <4cal>, <4gas>, and select the gas calibration on the molbloc to be
adjusted to read and record the current values of FA and FM.
 Press [ESC] several times to return to the main run display to see the real time flow
readings of the mobloc to be calibrated.
 Apply the calibration flow to the molbloc recording the flow applied by the standard andthe molbloc readings at each calibration point.
 Dwell at least 60 seconds after setting the reference flow at each point to allow
full stabilization. The data recorded is the "as received" data for this calibration.
 Enter the reference flow and molbloc flow readings for each point into a spreadsheet.
Calculate the "non-corrected" readings by backing out the as received FA and FM
recorded in Step  above, following:
non-corrected reading = (corrected reading - FA)/FM Perform a best fit linear regression to find the offset and slope that best fit the noncorrected flow readings to the calibration reference flows. Most commercial spreadsheet
products have a standard function to perform a linear regression. The offset, in thecurrent unit of measure, is the new value of FA, the slope is the new value of FM.
 Press [SPECIAL], <4cal>, <4gas>, and select the gas calibration on the molbloc to be
adjusted to write the new values of FA (always in the current unit of measure) and FM
and the new calibration date (YYYYMMDD) for the gas that is being calibrated.
 Calculate “as left data" for the calibration:
as left reading = (non-corrected reading • new FM) + new FA
 If desired, verify the as left data by rerunning the calibration with the new FA and FM
applied and checking that the disagreements between the calibration standard and the
RPT readings are in tolerance.

 Caution•

If at all possible, only use a value of FM to correct for slope changes of themolbloc in the calibrated gas and leave FA set to 0 at all times, as FA is anoffset value that does not ideally fit the % of reading design of a molbloc
calibration.

•

The value of FA must be entered in the flow unit of measure used to gather
the data. If the calibration data is in a different unit, the calculated value of
FA will be in the other unit and must be converted to the unit the data wasgathered in before it is entered.

•If you are not familiar or comfortable with the mathematics used for FA
and FM manipulation, it is recommended you verify the as left readings assuggested in Step  above to provide practical confirmation of theintegrity of the calculations. Note also that the CalTool for molbloc
Extension to COMPASS for Flow software performs the necessary
calculations automatically.

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5.6

Reloading Embedded Software Into molbox1+
Flash Memorymolbox1+ uses FLASH memory. This allows the embedded software that controls molbox1+ operations
and functions to be loaded into molbox1+ over its COM1 port from a personal computer with a simple
FLASH loading utility.
To replace corrupted software or upgrade to a new version, your Fluke Calibration Authorized Service
Provider can provide a FLASH memory loading utility along with a file containing the molbox1+ embedded
software.
These are also available for download from DHI’s worldwide web site,www.dhinstruments.com. An electronic copy of the current Operation and Maintenance Manual is alsoavailable on the website.
If the embedded software you are using is suspected of a problem, record all symptoms and contact your
Fluke Calibration Authorized Service Provider.

Note
The DHI flash software loading utility, molbox1+ embedded software and thecurrent Operation and Maintenance Manual are available for download from the“SOFTWARE” and “PRODUCTS” sections of Fluke Calibration’s worldwide website at www.dhinstruments.com.

5.7

Reloading molbloc EEPROM Filemolbloc EEPROMs are programmed with:•

A molbloc identifying header with range identifier, S/N and calibration date.

•molbloc specific flow calibration coefficients for N2, and other gases if entered.

•

The resistance at 0 °C of the molbloc platinum resistance thermometers (PRTs).

If the molbloc EEPROM information becomes corrupted, molbox1+ will be unable to read the molbloc
EEPROM and will display <NO BLOC> when attempting to initialize the molbloc.
Fluke Calibration maintains files of the “as shipped” EEPROM contents of every molbloc delivered orrecalibrated by Fluke Calibration. A molbloc EEPROM loading tool may be downloaded from the DHI
worldwide web site (www.dhinstruments.com) and specific molbloc files can be obtained by email. If you
believe you have a molbloc with a corrupted EEPROM, contact your Fluke Calibration Authorized
Service Provider for additional information on the molbloc EEPROM loading tool and obtaining molbloc
data files.

5.8

OVERHAUL Caution
If calibration of the Reference Pressure Transducers (RPTs) is included as part ofthe overhaul procedure, the calibration procedure should be performed last asother overhaul procedures may affect RPT calibration.

Any or all of the following items may be included as part of a system maintenance overhaul:•

Clean front panel.

•

Check that rear mounted cooling fan operates when molbox1+ is powered.

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5. MAINTENANCE, ADJUSTMENTS AND CALIBRATIONNote
To open the molbox1+ case, fold back the screw covers on the top and bottom of
the case. Then remove the eight case screws. Lift OFF the cover and bottom andplace the molbox1+ on its side for easy access to internal components.
•

Disassemble valving assembly and clean valve components.

•

Check that internal screws, bolts and nuts are tight.

•

Perform molbox1+ leak check (see Section 3.4.4.3) and verify operation by connecting a molbloc (seeSection 3.5.1).

•

Perform calibration of RPTs, if necessary (see Section 5.2).

•

Perform calibration of MFC control function if option present (see Section 5.3).

•

Verify ohmic measurement circuit if necessary (see Section 5.4).

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Notes© 2010 Fluke Calibration

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6.

Troubleshooting

6.1

Overview

molbox1+ is a sophisticated flow measuring instrument with advanced on-board features and functions.
Before assuming that unexpected behavior is caused by a system defect or breakdown, the operator
should use this manual and other training facilities to become thoroughly familiar with molbox1+
operation. This troubleshooting guide is intended as an aid in identifying the cause of unexpectedmolbox1+ behavior and determining whether the behavior is due to normal operation or an internal orexternal problem.
Identify the symptom or unexpected behavior you are observing from the SYMPTOM list in Table 42.
A PROBABLE CAUSE is provided and a SOLUTION is proposed including references to manual
sections that provide information that may be of assistance.
Table 42. Troubleshooting Checklist
SYMPTOMPROBABLE CAUSESOLUTION

Will NOT power up.

Blown fuse.

Replace fuse.

Front panel keys seem to bedisabled.

"Remote" command has been sentfrom a host computer locking out thefront panel keypad.

Operation is normal. Send "local" commandfrom host computer or cycle molbox1+
power. 4.2.2

Front panel display is dim.

Screen saver option has activated.

Operation is normal. Press any key toresume full screen power, adjust Screen
Saver activation time if desired. 3.6.5.1

Keypad presses make no sounds.

molbox1+ does not support key padsounds.

Operation is normal.

Cannot access certain functions.
Display shows:

User level setting restricts access tothat function.

Operation is normal. Change user level orconsult system manager. 3.6.2

Cannot establish communication
over remote interface.

Computer and/or molbox1+ interface
not correctly configured; incorrect or
bad interface cable.

Check and correct interface configurations
and cables if necessary. 3.6.6, 4.

molbox1+ unable to read molbloc.

Cable not connected, molbloc data
corrupted.

Check cable connections, try anothermolbloc, reload molbloc EEPROM. 3.5.1, 5.6

Displays <FATAL ERROR> or<FATAL FAULT>.

Encountered unresolved internal
software conflict.

Cycle power to clear. Record conditions
leading up to event including the numbers
displayed when [ENTER] is pressed and report
to Fluke Calibration Authorized Service
Provider. 7.4

Displays <PRT ERROR>.

molbox1+ has identified an unusuallylarge disagreement between thetemperature readings of the two
molbloc PRTs which may be due tofaulty molbloc PRTs or the molbox1+
ohmic measurement system.

Connect a different molbloc. If the PRT error
is no longer present, the PRT system of theoriginal molbloc is probably damaged andrequires service. If the PRT error is present
with different molblocs, the molbloc/molbox
cable or molbox1+ ohmic measurement
system is probably defective and requires
services. 3.4.5, 5.4

Display <TOUT> or <TIME-OUT>.

molbox1+ is having an internal
communications problem with one orboth of its RPTs.

Turn power off and back on and/or execute
Reset – Sets being careful to reenter desired
settings afterwards. If problem persists,
molbox1+ needs service. 3.6.1.1[P&T] key active only.

<ACCESS RESTRICTED>.

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Displays <NO BLOC>.

No molbloc is connected to molbox1+
or molbox1+ is unable to read themolbloc that is connected.

Verify proper electrical connection between
the molbox1+ and a valid molbloc. If <NO
BLOC> is observed with one molbloc and notothers, molbloc is damaged and/or EEPROM
is corrupted. 3.5.1, 5.6

Displays <******> where anumerical value should go.

Number to be displayed is too large forallocated space. Usually due to anerroneous setting or measurement
causing an out of limit value to be
calculated.

Check settings that may be causing an out oflimit measurement and adjust if necessary.
3.4.9, 3.4.1, 3.5.3

Bottom line of display has changed
and you want to change it back.

The DISPLAY function has been used
to change the display.

Use [DISPLAY] to set bottom line to desired
display. 3.4.6

Bottom line of display is blank.

DISPLAY mode is “clean”.

Operation is normal. Use [DISPLAY] tochange bottom line display if desired. 3.2.6.8,
3.4.6

Display is showing pressure values
and flashing, beeper is sounding
two second beeps.

Pressure applied to one or both of theabsolute RPTs is near overpressure.

Reduce pressure applied to upstream (HI)and downstream (LO) molbloc pressureconnection ports and cycle power onmolbox1+. 3.6.3.1, 1.2.2

Display is showing <OVERP!>.

One or both of the molbox RPTs has
been overpressured.

Remove the source of overpressure andpress [ENTER] to clear. Check molbox
RPTs for damage. 3.6.3.1, 1.2.2

Display is showing <BPR HI>
where the flow value should go.

molbox1+ is in molbloc-S mode and theratio of downstream pressure to
upstream pressure (B\PR) is to high tomake a valid flow measurement.

Operation is normal. Increase flow toincrease upstream pressure and/or decrease
downstream pressure. 3.1.5, 3.6.9

Flow indication is flashing in
molbloc-L mode

Flow is 5% or more beyond the
maximum flow for a named cal molbloc
gas calibration.

Operation is normal. Indicates that flow isbeyond the molbloc-L calibrated range
1.2.5.1.2, 1.2.5.1.3, 3.2

Flow indication is flashing in
molbloc-L mode

Pressure is 10kPa above the maximum
pressure or 10kPa below the minimumpressure for a named cal molbloc gas
calibration.

Operation is normal. Indicates that flow isbeyond the molbloc-L calibrated range
1.2.5.1.2, 1.2.5.1.3, 3.2

Flow indication is flashing in
molbloc-L mode

Reynolds number is greater than 1300

Operation is normal. Indicates that flow isbeyond the molbloc-L range 1.2.5.1.2,
1.2.5.1.3, 3.2

Flow indication is flashing in
molbloc-S mode

Flow is 5% or more beyond the
maximum flow for a named cal molbloc
gas calibration.

Operation is normal. Indicates that flow isbeyond the molbloc-S calibrated range
1.2.5.1.2, 1.2.5.1.3, 3.2

Flow indication is flashing in
molbloc-S mode

Pressure is 10kPa above the maximum
pressure or 10kPa below the minimumpressure for a named cal molbloc gas
calibration.

Operation is normal. Indicates that flow isbeyond the molbloc-S calibrated range
1.2.5.1.2, 1.2.5.1.3, 3.2

Flow indication is flashing in
molbloc-S mode

Back pressure ratio is too high toestablish critical flow through themolbloc-S.

Operation is normal. Increase molbloc-S
upstream pressure or reduce downstreampressure to reduce BPR below the BPR limit
at the current Reynolds numbers. 3.1.5,
1.2.5.2.1.

Flow indicated by molbox1+ never
becomes stable.

The flow through the molbloc is notstable.

The molbox1+ passively measures the flow
through the molbloc. It does not control flow.
Correct conditions that are causing unstableflow.

A Ready (<*>) indication is neverachieved in molbloc-L mode.

Flow stability criterion is never being
met and or Reynolds number limit of 1
200 is being exceeded.

Adjust stability criterion or stabilize flow.
Reduce the flow rate and/or pressure to
reduce the Reynolds number of the flow.
3.5.2

Ready (<*>) indication andmeasured flow value are flashingin molbloc-L mode.

The flow is within the stability limit but
the Reynolds number of the flow
exceeds the maximum acceptable limitof 1,200.

Operation is normal.

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Pressure indicated by molbox1+
never becomes stable.

There is a leak in the molbox1+ and/orin the system to which it and themolbloc are connected.

Find and correct leak. Consider using
molbox1+ LEAK CHECK functions. 3.4.4.3

Flow indication appears to be
grossly incorrect.

Your assumption of flow in the systemis grossly incorrect.

Check and adjust flow in the system.

Flow indication appears to be
grossly incorrect.

The molbloc connected to molbox1+
has been swapped without
reinitialization so molbox1+ is still using
characteristics from a previous molbloc.

Reinitialize molbloc using [SETUP],<1molbloc>. 3.5.1

In molbloc-S mode, there is noflow through the molbloc but
molbox1+ is indicating a large flow
value.

molbox1+ is in BPR OFF mode andflow is being calculated from upstream
absolute pressure without knowledge ofdownstream pressure.

Behavior is normal. Consider BPR whenevaluating flow measurements when using
molbloc-S. Also consider changing BPR
mode to Auto or ON. 3.1.5, 3.6.9, 3.4.4.5

Flow indication appears to beincorrect.

molbox/molbloc and/or the device you
are comparing it to are in tolerance but
you have not properly evaluated thetolerance limits.

Determine flow measurement tolerance ofmolbloc/molbox and device you arecomparing with. Evaluate “correctness”
relative to the combined tolerance of the two.
1.2.5.

Flow indication appears to beincorrect.

Reference pressure transducer(s)(RPTs) are inoperable or out ofcalibration.

Use [P&T] to view pressure indications.
Recalibrate RPTs if necessary. 3.4.5, 5.2

Flow indication appears to beincorrect.

The gas selected is not the gas flowing
through the molbloc.

Select the correct gas. 3.4.2

Flow indication appears to beincorrect while using molbloc-S tomeasure air flow

Incorrect humidity ratio is being used.

Reselect Air as the test gas and make surethe humidity ratio W is entered properly. W
should be zero for dry air and should be
calculated from ambient conditions whenmeasuring ambient air. 3.4.2.2.

Flow indication appears to beincorrect.

The gas selected is the gas flowing
through the molbloc but the molbloc
has not been calibrated for that gas.

Verify that the molbloc has calibration
coefficients for the flowing gas, have themolbloc calibrated for the flowing gas if
necessary or accept higher measurement
uncertainty in the flow measurements. 3.5.1,
1.2.5

Flow indication appears to beincorrect.

Gas flowing through molbloc is not
pure.

Check purity rating of gas used; purge
molbox/molbloc if flowing gas was justchanged. If gas is a known mix, use the flow
adder and multiplier to correct for the mix.
3.4.4.2, 3.5.3

Flow indication appears to beincorrect.

The molbloc is not being used at thecorrect pressure for its pressure
dependent calibration type.

Check molbloc Calibration Report forpressure dependent calibration type andcheck operating pressure. 1.2.5, 3.2.5

Flow indication appears to beincorrect.

molbox1+ pressure and/or Reynolds
numbers are outside of limits.

Observe pressure and Reynolds numbers
and adjust pressure/flow to be inside oflimits. 1.2.5, 3.4.5

Flow indication appears to beincorrect.

Flow through molbloc is in wrong
direction.

Check that flow through molbloc is in
direction of arrow on molbloc. Switch if
necessary.

Flow indication appears to beincorrect.

Leak in pressure lines from molbloc tomolbox1+.

Check lines for leaks and correct ifnecessary. 3.4.4.3

Flow indication appears to beincorrect.

A flow adder or multiplier has been
incorrectly or inadvertently applied.

Check and correct if necessary. 3.5.3

Flow indication appears to beincorrect.

molbloc calibration has changed due tocontamination.

Check molbloc for contamination. Contact
your Fluke Calibration Authorized Service
Provider if liquid or particulate contamination
is detected. 7.4

Flow indication appears to beincorrect by a constant offset
amount.

molbox1+ needs to be correctly“zeroed” (tared) at the current operatingpressure.

Tare molbox1+. Be sure to tare upstream if
the upstream pressure is constant anddownstream if the downstream pressure isconstant. 3.4.4.1

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Flow indication appears to beincorrect and molbloc is upstream
and reading high.

Leak downstream of molbloc.

Check for and correct leak if present.
Consider using molbox1+ SYSTEM LEAKCHECK function. 3..4.3

Flow indication appears to beincorrect and flow rate is less than
50 sccm.

Flow in system is not in steady state;
too much volume between molbloc andtest; unstable pressure on molbloc.

Be sure flow is stable before reading, reduce
dead volumes, install precision regulator,
consider using DHI low flow molstic.

Flow indication appears to beincorrect and flow unit is a
volumetrically based mass flow
unit (sccm, scfh, etc.).

Reference temperature orcompressibility consideration involumetrically based units isinconsistent.

Set units correctly for consistency between
values being compared. Be sure to select aunit starting in “u” for volumetrically basedmass flow units if reference temperature is
not 0 °C. 3.4.3, 3.4.3.3

Unable to make molbloc-S flow
measurements over full expected
flow range

MFC or flow control valve is connected
dowsntream of molbloc-S

Valve or regulator used to control flow
through molbloc-S must always be upstreamof the molbloc-S. When operating an MFC
with molbloc-S, the MFC must always be
upstream.

Unable to make molbloc-S flow
measurements over full expected
flow range

molbloc-S back pressure too highThe downstream pressure on molbloc-S must
always be significantly lower than the
upstream pressure to maintain critical flow.
When upstream pressure is reduced, theback pressure ratio may become too high tomake valid flow measurements. 3.1.5

Unable to make molbloc-S flow
measurements over full expected
flow ranges.

Flow units use reference temperatureother than 0° C.

The molbloc-S flow range tables display flow
ranges expressed in slm @ 0° C. If you use
volumetrically based flow units with anotherreference temperature, the minimum usable
flow value may be increased by up to 9% fora given molbloc-S downstream pressure.
1.2.5.2.1, 3.4.3.3, tables 4 to 14

Unable to reach molbloc-S
maximum flow

Pressure regulator supplying molbloc-S
set too low.

If you are controlling flow with a control valve
downstream of a fixed pressure regulator,
you must have sufficient pressure supply
pressure to reach the maximum desired
molbloc-S flow. Be sure not to exceed
molbox1+ maximum operating pressure.
1.2.5, 2.3.4

Flow indication appears to beincorrect and flow unit is a volume(actual) flow unit (ccm, cfh, etc.).

Volume flow pressure and/or
temperature is/are incorrect.

Set more accurate values for volume flowpressure and/or temperature. 3.4.3.1, 3.4.3.4

Flow indication appears to beincorrect and there is a K following
the flow unit on the display.

A K factor is being applied incorrectly or
inadvertently.

Turn off or correct K factor. 3.4.1

Flow indication appears to beincorrect and you are using
AVERAGING function.

Averaging period is wrong and does notcorrespond to reading period of thedevice you are comparing with.

Adjust averaging period and/or be sure tosynchronize averaging period of themolbox1+ and the device you are comparing
to. 3.4.6.2

Flow indication is negative.

Flow in your system is reverse fromwhat you expect; molbloc upstream anddownstream pressure lines are
switched.

Check system and correct flow; checkpressure lines and switch if necessary.

Pressure transducer (RPT)
indications are out of range.

Incorrect RPT calibration coefficients;
RPT(s) has (have) been overpressured.

Correct calibration coefficients; havetransducers replaced if damaged. 5.2

molbloc-S Tare does not executeas expected

Expectation of tare function operation isincorrect for molbloc-S.

Normal molbox1+ operation. The molbloc-S
tare function has a different purpose andmethod of operation from molbloc-L tare anddoes not require saving a fixed tare value.
3.4.4.1.2

Cannot tare molbox due toexcessive tare value.

One or several RPTs are defective;
RPT calibration is bad; there is a leakinside molbox1+ causing a differential
pressure.

Check performance of RPTs; checkcalibration of RPTs; leak check molbox1+.
5.2© 2010 Fluke Calibration

Page 160

6. TROUBLESHOOTINGSYMPTOMPROBABLE CAUSESOLUTION

Leak check does not indicate
pass/fail in molbloc-S operation.

Improper expectation for molbloc-S
leak check..

Normal molbox1+ operation. molbloc-S
system leak check function in molbox1+ does
not have pass/fail criteria assigned as
molbloc-L leak check does. 3.4.4.3

Measured pressure display has
too much/not enough resolution.

Resolution setting needs to bechanged.

Use [RES] to change resolution setting. 3.4.9

Flow rate is changing but displayof flow is not and the bottom righthand corner of the display is anumerical countdown followed by<avg>.

AVERAGE DISPLAY function is ON
and pressure display is updating onlywith the average value at the end ofeach averaging cycle.

Go to a DISPLAY function other than
AVERAGE or press [+/-] to get the
instantaneous value AVERAGE DISPLAY.
3.4.6.2

Current flow through the molbloc iszero but reading is not zero inmolbloc-L operation.

Need to run TARE function to zeromolbox1+ RPTs.

Run TARE. 3.4.4.1.1

Poor flow measurement
characterized by instability andsudden small jumps in flow rate.

The molbox1+ pneumatic circuit iscontaminated with liquids.

Purge and clean molbox1+ and associatedpneumatic systems. Contact your Fluke
Calibration Authorized Service Provider. 7.4

Grossly inaccurate flow
measurements and little or no
response to pressure or flowchanges.

RPT(s) destroyed by overpressure.

View pressure readings using [P&T]. If
readings are grossly inaccurate and don’t
respond to pressure changes, contact your
Fluke Calibration Authorized Service
Provider. 3.4.5, 3.1.4, 5.2, 7.4

Apparent inaccurate pressure
measurement.

Incorrect pressure units.

Set desired pressure units. Consider
reference temperature if unit is inWa. 3.5.8

Apparent inaccurate pressure orflow measurement.

Reference pressure transducer (RPT)
calibration coefficients have beenaltered or lost and pressure
measurements are incorrect.

Check and correct calibration coefficients ifneeded. 5.2

MFC connected to molbox1+
doesn’t appear to be responding.

MFC control option is not implemented
on this molbox1+.

Check whether molbox1+ MFC control option
was ordered and installed.

MFC connected to molbox1+
doesn’t appear to be responding.

The MFC control function is not active(OFF).

Activate MFC control function by selecting achannel other than zero. 3.4.8

MFC connected to molbox1+
doesn’t appear to be responding
correctly.

molbox1+ to MFC control cable is notconnected or connected incorrectly.

Check MFC cable connection and MFC cableconfiguration. 7.3

MFC value and/or molbox1+ flow
values appear incorrect.

MFC profile does not correspond to
MFC in use.

Check MFC profile and create and/or selectcorrect one. 3.4.8.2, 3.5.5

MFC seems to be adjusting to set
the requested flow value as readby the molbox.

MFC regulation mode is ON.

Operation is normal. Turn MFC regulation
mode OFF. 3.5.6

MFC value and/or molbox1+ flow
values appear incorrect.

Incorrect or inadvertent use of K factor
and/or gas selection.

Check K factor and gas selection and correct
if necessary. 3.4.1, 3.4.2[ENTER] is not going to MFC set
point screen. Cannot get to MFC
set point entry.

The MFC control option is not
implemented on this molbox or thecurrent DISPLAY mode does notsupport MFC set point entry.

Check whether molbox1+ MFC control option
was ordered and installed. If MFC control
option is present, use [DISPLAY] to set
DISPLAY mode to RATE, UNIT or CLEAN.
3.4.6

Page 161© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Notes© 2010 Fluke Calibration

Page 162

7.

Appendix

7.1

Conversion of Numerical Values

molbox1+ performs all internal calculations in SI units. Numerical values input or output in other units areconverted to SI immediately after entry and back to other units just before output as needed.
The tables below provide the conversion coefficients used by molbox1+ to convert numerical values
expressed in SI units to corresponding values expressed in other units.

7.1.1

Pressure
Table 43. Pressure Unit Conversions
TO CONVERT FROM PA TO
Pa

Pascal

1.0

Mbar

Millibar

1.0 E-02

KPa

kilo Pascal

1.0 E-03

BarBar

1.0 E-05mmWa @ 4 °C

Millimeter of water

1.019716 E-01

mmHg @ 0 °C

Millimeter of mercury

7.50063 E-03

Psi

pound per square inch

1.450377 E-04

Psf

pound per square foot1.007206 E-06

inWa @ 4 °C

inch of water

4.014649 E-03

inWa @ 20 °C

inch of water

4.021732 E-03

inWa @ 60 °F

inch of water

4.018429 E-03

inHg @ 0 °C

inch of mercury

2.953 E-04

2

Kilogram force per centimeter square

1.019716 E-05

User

User

User defined coefficient

kcm

7.1.2

MULTIPLY BY

Temperature
Table 44. Temperature Unit Conversion
TO CONVERT FROM °C TO

MULTIPLY BY°F

9/5 and add 32

Page 163© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

7.1.3

Flow
Table 45. Conversions from kg/s to sccm at 0 °C for Various Gases
TO CONVERTFROM KG/S TO SCCM AT 0 °C

MULTIPLY
BY

Air (Air)

4.64109 E+07

Argon (Ar)3.36398 E+07

Butane (C4H10)

2.22112 E+07

Carbon Dioxide (CO2)

3.03490 E+07

Carbon Monoxide (CO)4.79862 E+07

Carbon Tetrafluoride (CF4)

1.52386 E+07

Ethane (C2H6)

4.42602 E+07

Ethylene (C2H4)

4.75813 E+07

Fluoroform (CHF3)

1.90128 E+07

Helium (He)3.36210 E+08

Hexafluoroethane (C2F6)

9.60432 E+06

Hydrogen (H2)

6.67483 E+08

Methane (CH4)8.36354 E+07

Nitrogen (N2)

4.79808 E+07

Nitrous Oxide (N2O)

3.03321 E+07

Oxygen (O2)

4.19903 E+07

Propane (C3H8)

2.98516 E+07

Sulfur Hexafluoride (SF6)9.06602 E+06

Xenon (Xe)

1.01710 E+07

Table 46. Conversions from sccm at 0 °C to Other Volumetrically Based Flow Units
TO CONVERTFROM SCCM AT 0 °C
TO OTHERVOLUMETRICALLY BASED
UNITS© 2010 Fluke Calibration

Page 164

MULTIPLY
BY

Slm

1.0 E-03

Slh

6.0 E-02

Scfm

3.53147 E-05

Scfh

2.11888 E-03

Sm3m

1.0 E-06

Sm3h

6.0 E-05

7. APPENDIX

Table 47. Conversions from Volumetrically Based Flow Units at 0 °C to
Corresponding Units at Another Temperature (uxxx)
TO CONVERT VOLUMETRICALLY BASED UNITS
AT 0 °C TO CORRESPONDING UNITS AT
ANOTHER TEMPERATURE, Θ, (UXXX)MULTIPLY BY

sccm
slm
slh
scfm

(TN + θ) ⋅ Ζ (PN ,( TN +θ))TN ⋅ Ζ N

scfh
sm3m
sm3h

Where: θ = Alternate reference flow temperature [K].
TN = 273.15K
PN = 101325 Pa

Z (PN ,(TN +θ )) ;Z N gas dependent compressibility factors
Table 48. Conversions from kg/s to mole/s for Various Gases
TO CONVERT KG/SEC TO
MOLE/S

MULTIPLY
BY

Air (Air)

3.45316 E+01

Argon (Ar)2.50325 E+01

Butane (C4H10)

1.72049 E+01

Carbon Dioxide (CO2)2.27221 E+01

Carbon Monoxide (CO)3.57015 E+01

Carbon Tetrafluoride (CF4)

1.13624 E+01

Ethane (C2H6)

3.32568 E+01

Ethylene (C2H4)

3.56455 E+01

Fluoroform (CHF3)

1.42837 E+01

Helium (He)2.49838 E+02

Hexafluoroethane (C2F6)

7.24533 E+00

Hydrogen (H2)

4.96032 E+02

Methane (CH4)6.23325 E+01

Nitrogen (N2)

3.56939 E+01

Nitrus Oxide (N2O)

2.27206 E+01

Oxygen (O2)

3.12512 E+01

Propane (C3H8)

2.26778 E+01

Sulfur Hexafluoride (SF6)6.84697 E+00

Xenon (Xe)7.61615 E+00

Table 49. Conversion from mole/s to pccm
TO CONVERT MOLE/SEC
TO PCCM
Any GasPage 165

MULTIPLY
BY
1.34483 E+06

© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Note
The “p” in pccm indicates “perfect” in which a gas compressibility factorof 1 is assumed for all gases. In early 1996, SEMI, a semiconductor
industry group, adopted standard E12-96 which specified that thisdefinition be used for volumetrically base mass flow units.
Table 50. Conversion from sccm at 0 °C
to Volume Flow Units at Another Pressure and Temperature
TO CONVERT FROM A VOLUMETRIC MASSFLOW UNIT TO THE EQUIVALENT VOLUMEFLOW UNIT AT TEMPERATURE θ AND PUSER

MULTIPLY BY

sccm to ccm
slm to lm
slh to lhs
cfm to cfm
scfh to cfh(TN + θ) ⋅ Ζ (PN ,( TN +θ))TN ⋅ Ζ N

sm3m to m3m
sm3h to m3h

Where:

TN = 27315. K
Puser = user pressure [kPa]θ = user temperature [K]PN = 101.325 kPaz(Puser ,( TN +θ )) ; zN = gas dependent compressibility factors

7.2

Valve Drivers

The molbox1+ drivers option provides eight open collector drivers for operating external valves,solenoids, indicators, etc. When operating from the setup-driver screen, pressing enter will allow theoperating mode of the drivers to be set. The two modes of operation are Momentary and Toggle.
A momentary driver will be activated while the corresponding driver number on the keyboard isbeing pressed. In toggle mode the driver state will toggle each time the corresponding key is pressed.
Each output can sink,500 mA at 12 V. However, the total output of all the activated drivers cannot
exceed 1 Amp. Therefore, if multiple drivers are being activated please refer to Table 51 as a guide.
Table 51. Driver/Max Current Per Output© 2010 Fluke Calibration# OF ACTIVE
DRIVERSMAX CURRENTPER OUTPUT

1

500 mA2

400 mA3

275 mA

4

200 mA5

160 mA6

135 mA7

120 mA

Page 166

7. APPENDIX

8

100 mA

Table 52 and Figure 16 should be used as reference when building a cable to utilize the drivers port.
Table 52. External Drivers
PIN

DESCRIPTIONA

D1

Driver #1 (Open Collector)

C

D2

Driver #2 (Open Collector)

E

D3

Driver #3 (Open Collector)

G

D4

Driver #4 (Open Collector)

M

D5

Driver #5 (Open Collector)

J

D6

Driver #6 (Open Collector)

K

D7

Driver #7 (Open Collector)

L

D8

Driver #8 (Open Collector)

B

Drivers (+12 V)

D

Drivers (+12 V)

F

Drivers (+12 V)

H

Drivers (+12 V)

Figure 16. Cable Driver Ports

Page 167© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

7.3

MFC Control Function
7.3.1

MFC Connector

Table 53 should be used to correctly build the interfacing cable required to connect themolbox1+ to an MFC.
Table 53. Interface Cable Building Instructions
MOLBOX1+ MFC
INTERFACECONNECTOR (25 PIN
DSUB) PIN NO.

7.3.1.1© 2010 Fluke Calibration

SIGNAL DESCRIPTION

1

Case Ground2

Supply Common

3

MFC Output (+)

4+15 Volts

5

N/C

6

N/C

7

Set Point Sense (-)

8

N/C

9

N/C

10

N/C

11

Valve Test

12

Current MFC Output (+)

13

Current MFC Set (+)

14

MFC Setpoint (+)

15

MFC Setpoint (-)

16

MFC Output (-)

17

Valve Test Common

18

N/C

19

-15 Volts

20

Set Point Sense (+)

21

N/C

22

N/C

23

N/C

24

RS485 TXRX+

25

RS485 TXRX-

Detailed Signal Descriptions•+15 Volts: This is the positive 15 Volt supply for the MFC.

•

-15 Volts: The negative 15 Volt supply for the MFC.

•

Current MFC Output (+): This signal is only used for current controlled
MFCs. This is the 4-20 mA signal that represents the MFC’s output.

Page 168

7. APPENDIX•

Current MFC Set (+): This signal is only used for current controlled MFCs.
This is the 4-20 mA signal that defines the desired setpoint for the MFC. It isfrequently referred to as the MFC control signal or the MFC setpoint.

•

MFC Output (+): This is the positive 0 to 5 Volt signal that represents the
MFC’s output. It is commonly referred to as “output” or “signal output”.

•

MFC Output (-): This is the ground reference for the MFC output signal. Itis frequently referred to as “Signal Common”, or “Common”.

•

MFC Setpoint (+): This is the desired setpoint for the MFC. It is the signalthat controls the amount of gas that the MFC will flow. It is generally a 0 to 5
Volt signal where 0 Volt signal causes the valve to close (zero flow) and 5
Volt signal cause the valve to open fully resulting in full scale flow. Thissignal is commonly referred to as “MFC set point”, “MFC set voltage”, “MFC
command”, or “MFC control”.

•

MFC Setpoint (-): This is the ground reference for the MFC Setpoint signal.
It is frequently referred to as “Signal Common”, or “Common”.

•

N/C: This abbreviation stands for no connection. There are no signals on
the lines marked N/C.

•

RS485 TXRX+: This is the RS485 TXRX+ signal. It is used to communicate
with digital MFCs using the RS485 communications protocol. The RS485
signals are also available on the phone jack style connector on themolbox1+.

•

RS485 TXRX-: This is the RS485 TXRX+ signal. It is used to communicate
with digital MFCs using the RS485 communications protocol. The RS485
signals are also available on the phone jack style connector on themolbox1+.

•

Set Point Sense (+): This signal is used by the molbox1+ to detect loss
along the MFC cable. It represents the positive MFC set point as seen by
the MFC. This line should be connected to the same point as the MFC
Setpoint (+) line at the MFC side of the cable.

•

Set Point Sense (-): This is the ground reference for the MFC Setpoint
sense. It should be connected to the same point as the MFC setpoint (-) line.

•

Supply Common: This is the ground line for the MFC’s power connection.
It is frequently referred to as “Power Common”, “Supply Common”, or just“Common”.

•

Valve Test: This optional connection is used to read the valve test point
signal coming from the MFC. If this signal is available at the MFC connector,
it allows the user to read the internal voltage delivered to the MFC valve.

•

Valve Test Common: This is the reference for the valve test signal. It may
be connected to a common line or the –15V line of the MFC, depending on
the instructions of the MFC manufacturer for valve voltage measurement.

7.3.1.2

Popular Configurations

The following configuration can be used with most card edge style MFCs.
Any differences tend to relate to the handling of the ground (common) lines (pins 2,
B and C). Most cable problems can be resolved by either shorting pins B and C
or by swapping the signals connected to pin 2 of the card edge connector withthe signals connected to pin B of the card edge connector. The configuration
below should work with the following MFCs.
•

Millipore (Tylan) model FC260, 261, 262, FM 360, 361, 362•

Qualiflow AFC 260, 261, 202, 360, 361, 302
Page 169© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL•

Aera 2600, 2610, 2620, 3600, 3610, 3620•

PFD 501•

Porter 201•

Unit Instruments models UFC 1000,1020, 1100,1200, 1400, 1500
Table 54. Common MFC Connector Pin Out
MOLBOX1+ MFC
INTERFACECONNECTOR(25 PIN DSUB)PIN NO.

SIGNALDESCRIPTIONMFC CARD EDGE
CONNECTOR PIN
NOS.

1Case Ground

1 (A1)

2

Supply Common

2 (A2)

3

MFC Output (+)

3 (A3)

4+15 Volts

4 (A4)

7

Set Point Sense (-)

B (B2)

11

Valve Test

D (Optional) (B4)14

MFC Setpoint (+)

A (B1)

15

MFC Setpoint (-)

B (B2)

16

MFC Output (-)

C (B3)

17

Valve Test Common

F (Optional) (B6)19-15 Volts

F (B6)

20

Set Point Sense (+)

A (B1)

The following configuration can be used with:•

Brooks model 5850E, and 5851E
Table 55. Brooks MFC Connector Pin Out
MOLBOX1+
MFC INTERFACECONNECTOR(25 PIN DSUB)PIN NO.

© 2010 Fluke Calibration

SIGNALDESCRIPTIONMFC CARDEDGE
CONNECTORPIN NOS.

MFC 15 PIN DSUB
CONNECTOR PIN
NOS.

1Case Ground

1 (A1)

14

2

Supply Common

C (B3)

9

3

MFC Output (+)

3 (A3)

2

4+15 Volts

4 (A4)

5

7

Set Point Sense (-)

2 (A2)

10

11

Valve Test

D (Optional) (B4)

7 (Optional)

14

MFC Setpoint (+)

A (B1)

8

15

MFC Setpoint (-)

2 (A2)

10

16

MFC Output (-)

B (B2)

10

17

Valve Test Common

F (Optional) (B6)

10 (Optional)

19-15 Volts

F (B6)

6

20

Set Point Sense (+)

A (B1)

8

Page 170

7. APPENDIX

7.4

Limited Warranty and Limitation of Liability

Each Fluke product is warranted to be free from defects in material and workmanship under normal use and service.
The warranty period is one year and begins on the date of shipment. Parts, product repairs and services are
warranted for 90 days. This warranty extends only to the original buyer or end-user customer of a Fluke authorized
reseller, and does not apply to fuses, disposable batteries or to any product which, in Fluke's opinion, has been
misused, altered, neglected, contaminated, or damaged by accident or abnormal conditions of operation or handling.
Fluke warrants that software will operate substantially in accordance with its functional specifications for 90 days andthat it has been properly recorded on non-defective media. Fluke does not warrant that software will be error free oroperate without interruption.
Fluke authorized resellers shall extend this warranty on new and unused products to end-user customers only but
have no authority to extend a greater or different warranty on behalf of Fluke. Warranty support is available only if
product is purchased through a Fluke authorized sales outlet or Buyer has paid the applicable international price.
Fluke reserves the right to invoice Buyer for importation costs of repair/replacement parts when product purchased in
one country is submitted for repair in another country.
Fluke's warranty obligation is limited, at Fluke's option, to refund of the purchase price, free of charge repair, or
replacement of a defective product which is returned to a Fluke authorized service center within the warranty period.
To obtain warranty service, contact your nearest Fluke authorized service center to obtain return authorization
information, then send the product to that service center, with a description of the difficulty, postage and insurance
prepaid (FOB Destination). Fluke assumes no risk for damage in transit. Following warranty repair, the product will
be returned to Buyer, transportation prepaid (FOB Destination). If Fluke determines that failure was caused byneglect, misuse, contamination, alteration, accident or abnormal condition of operation or handling, including
overvoltage failures caused by use outside the product’s specified rating, or normal wear and tear of mechanicalcomponents, Fluke will provide an estimate of repair costs and obtain authorization before commencing the work.
Following repair, the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the
repair and return transportation charges (FOB Shipping Point).
THIS WARRANTY IS BUYER'S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES,EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY
OR FITNESS FOR A PARTICULAR PURPOSE. FLUKE SHALL NOT BE LIABLE FOR ANY SPECIAL, INDIRECT,INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSSES, INCLUDING LOSS OF DATA, ARISING FROM ANY
CAUSE OR THEORY.
Since some countries or states do not allow limitation of the term of an implied warranty, or exclusion or limitation ofincidental or consequential damages, the limitations and exclusions of this warranty may not apply to every buyer. If
any provision of this Warranty is held invalid or unenforceable by a court or other decision-maker of competentjurisdiction, such holding will not affect the validity or enforceability of any other provision.
Fluke Corporation
P.O. Box 9090
Everett, WA 98206-9090
U.S.A.

Fluke Europe B.V.
P.O. Box 1186
5602 BD Eindhoven
The Netherlands

Page 171© 2010 Fluke Calibration

molbox1+™/molbox1+S, molbloc® TERMINAL OPERATION AND MAINTENANCE MANUAL

Table 56. Fluke Calibration Authorized Service Providers
FLUKE CALIBRATIONAUTHORIZED SERVICE PROVIDERS – PRESSURE CALIBRATION PRODUCTS
COMPANYTELEPHONE,
FAX & EMAILADDRESSNORMAL SUPPORTREGION

Fluke Calibration

4765 East Beautiful Lane
Phoenix AZ 85044-5318
USA

Tel: 602.431.9100
Fax: 602.431.9559
dhiservice@fluke.com

Worldwide

Minerva Meettechniek B.V.

Chrysantstraat 1
3812 WX Amersfoort
The Netherlands

Tel: 31 33 46 22 000
Fax: 31 33 46 22 218
info@minervaipm.com

European Union

europascal GmbHAn der Wiesenhecke 10
D-63456 Hanau
Germany

Tel: +49 61 81 42 309 0
Fax: +49 61 81 42 309 22

European Union258-1, Nakadai
Kasumigaura-machi,
Niihari-Gun,
Ibaraki 300-0133
Japan

Tel: 81/29.840.9111

Fluke Beijing Service
CenterRm. 401, SCITEC Tower,
N0. 22, Jianguomenwai Dajie,
Beijing 100004, PRC

Hot Line: 400.810.3435-3
Fax:(8610) 65286307
serviceinfo@fluke.com.cn

Peoples Republic of China

Fluke South East Asia
PTE LTD.

Fluke ASEAN Regional OfficeService Center
60 Alexandra Terrace #03-16
The Comtech (Lobby D)
118502Singapore

Tel: (65) 6799-5588
Fax: (65) 6799-5589
service.asean@fluke.com

South East Asia

Ohte Giken Inc
Technology Center© 2010 Fluke Calibration

service@europascal.deJapan/Asia

Fax: 81/29.840.9100
tech@ohtegiken.co.jp

Page 172

8.

Glossary

Absolute

As in “absolute pressure”. Pressure expressed relative to vacuum.

BPR

Back Pressure Ratio. The ratio of the downstream pressure to the upstream pressure on amolbloc-S critical flow based molbloc element. The BPR is used to determine whether
Critical Flow conditions exist so that molbloc-S flow measurements are valid.

Critical flow

Also known as “sonic flow”. Flow regime where the speed of gas is accelerated to a velocity
equal to the speed of sound under current conditions and the flow rate can be predicted bymeasurement of the upstream pressure at the flow restriction (nozzle), the gas pressure andtemperature conditions and the gas properties.

Clean

A DISPLAY function in which the second line of the display is blank (clean).

Deviation

A DISPLAY function in which the deviation from a target flow value is calculated anddisplayed. The value of the difference between the target and the current flow reading.

Differential

As in “differential pressure”. Pressure expressed relative to a value other than vacuum or
atmospheric pressure (see absolute and gauge). Frequently refers to the pressure drop
across the molbloc.

Downstream

Location of point A relative to point B in a flow system in which point A is at a different
location in the direction of the flow. For example, the downstream molbloc pressure port isdownstream relative to the upstream pressure port because it is at a different location fromthe upstream port in the direction of the flow.

DUT

Device Under Test. The device being tested or calibrated.

FA (Flow Adder)

Flow adder. A value that is added to the measured flow to offset the measured flow value.

FM (Flow Multiplier)

Flow multiplier. A value by which the measured flow is multiplied to change the slope of themeasured flow.

FreezeA DISPLAY function in which the current flow reading can be captured and displayed bypressing [ENTER].

Full Mod Calibration

A molbloc calibration option which is valid over a range of operating pressure.

FS

Abbreviation of "full scale". The full scale value is the maximum value or the span of ameasurement range. Limits and specifications are often expressed as % FS.

Gauge

As in “gauge pressure”. Pressure expressed relative to atmospheric pressure.

Head

The differential pressure developed by differences in height between two points within a fluid
medium.

Hi/Lo

A DISPLAY function in which the highest and lowest flow observed since hi/lo reset arerecorded and displayed.

K Factor

A factor representing the relationship between the process gas and a surrogate gas for a DUT.

Operating Pressure

The average pressure at which the molbloc is operated (average of upstream anddownstream pressure) or, if the molbloc pressure is held constant by an upstream or
downstream regulator, the value of the constant pressure.

PA (Pressure Adder)

Pressure adder, used in calibration adjustment to offset an RPT.

Perfect Mass Flow Units

Volumetrically based mass flow units of measure that assume ideal gas behavior for allgases (compressibility factor of 1).

PM (Pressure Multiplier)Pressure multiplier, used in calibration to adjust span of an RPT.

Pmax!

The overpressure limit of an RPT. If the pressure measured exceeds (Pmax!) an
overpressure condition occurs.

Process Gas

The gas for which a device under test (DUT) is to be characterized or calibrated. The gasthat will actually flow in the DUT when it is used in a process.

PRT

Platinum Resistance Thermometer. The element used in molblocs to measure temperature.

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Psia

Pressure unit “pounds per square inch absolute”. Pressure expressed relative to vacuum.

Psig

Pressure unit “pounds per square inch gauge”. Pressure expressed relative to atmosphericpressure.

Rate

A DISPLAY function in which the current rate of change of the flow in flow units/second isdisplayed. A measure of stability of the flow. See also Stability Limit.

Ready/Not Ready

Indication of when flow is stable within the stability limit and below the flow Reynolds number
limit. See also Stability Limit.

Reynolds Number

A ratio of the inertia forces to the viscous forces in a flowing fluid. This dimensionless
number, which is dependent on fluid viscosity, density, velocity and length of the flow field, isoften used to predict a boundary point between laminar and turbulent flow regimes.

RPT

Reference Pressure Transducer. The pressure transducers used in molbox1+ are referred
to as RPTs.

Single P Calibration

A molbloc calibration option for gases other than N2 which is valid at a single specified
operating pressure.

Stability Limit

A limit expressed in units of flow per second (e.g., sccm/second). The stability limit is usedas the Ready/Not Ready criterion Ready (<*>) if rate is less than stability limit, Not Ready(<↑> or <↓>) if rate is greater than stability limit. See also Rate.

Surrogate Gas

A gas whose behavior, from the standpoint of a device under test, is similar to the process
gas for which the device is to be characterized and used. A surrogate gas is often used incalibration and testing when the process gas cannot be used for safety or cost reasons.

Target

The value from which deviations are measured in the DEVIATION DISPLAY function.

Test Gas

The gas flowing through the molbloc that is being used to run the test or calibration.
The test gas, from the standpoint of the device under test, could be a surrogate gas or
the process gas.

Totalize

A DISPLAY function in which the total mass or volume flowed over a period of time isaccumulated.

Upstream

Location of point A relative to point B in a flow system in which point A is at a different
location in the opposite direction of the flow. For example, the upstream molbloc pressure
port is upstream relative to the downstream pressure port because it is at a different locationfrom the downstream port in the opposite direction of the flow.

User Level

Level of security that can be set to prevent access to certain molbox1+ functions.

User Mass Flow Units

Volumetrically based mass flow units of measure with a user set reference temperature.

Venturi nozzle

A flow orifice using a specific shape characterized by a convergent and divergent section,used to define flow measurements by measurement of flow conditions and gas properties.
A critical flow Venturi nozzle is a Venturi nozzle used to define flows within the Criticalflow regime.

Volume Flow Pressure

The absolute pressure of the flowing gas at the device under test for volume flow unitsof measure.

Volume Flow Temperature

The temperature of the flowing gas at the device under test for volume flow units of measure.

Volume Flow Units

Units of measure of volume (sometimes called “actual”) flow.

© 2010 Fluke Calibration

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