DIGITAL PRESSURE CONTROLLER
MODEL 7050
MODEL 7050i
MODEL 7050LP
USER’S MANUAL

RUSKA INSTRUMENT CORPORATION
10311 WESTPARK DR., HOUSTON, TEXAS 77042(713) 975-0547 FAX: (713) 975-6338
e-mail: ruska@ruska.com http://www.Ruska.com

Release: 7050-1D01
Revision: A
Date: 06/09/02-1-

INTRODUCTIONWARRANTY
Ruska Instrument Corporation warrants its products to conform to or exceed thespecifications as set forth in its catalogs in use at the time of sale and reserves the right,
at its own discretion, without notice and without making similar changes in articles
previously manufactured, to make changes in materials, designs, finish, or specifications.
Ruska Instrument Corporation warrants products of its own factory against defects ofmaterial or workmanship for a period of one year from date of shipment.
Liability of Ruska Instrument Corporation under this warranty shall be limited toreplacing, free of charge (FOB Houston, Texas), any such parts proving defective within
the period of this warranty, but will not be responsible for transportation charges orconsequential damages.
This warranty is not made for products manufactured by others which are illustrated anddescribed in Ruska catalogs or incorporated in Ruska products in essentially the same
form as supplied by the original manufacturer. However, Ruska Instrument Corporationagrees to use its best efforts to have original suppliers make good their warranties.

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INTRODUCTION

COPYRIGHT NOTICE
Copyright © 2003 by Ruska Instrument Corporation. All rights reserved. This document
may not be reproduced in part or in whole without the express written consent of Ruska
Instrument Corporation.

DISCLAIMER
No representations or warranties are made with respect to the contents of this user’s
manual. Further, Ruska Instrument Corporation reserves the right to revise this manualand to make changes from time to time in the content hereof without obligation to notify
any person of such revision.

TRADEMARK NOTICE® is a registered trademark of Ruska Instrument Corporation.
Trademarks or tradenames are subject to state and federal laws concerning theirunauthorized use or other infringements. The fact that the product marks or names in thismanual do not bear a trademark symbol DOES NOT mean that the product name ormark is not registered as a trademark or tradename. Any queries concerning theownership or existence of any trademarks or tradenames mentioned in this manual
should be independently confirmed with the manufacturer or distributor of the product.

-ii-

INTRODUCTIONREVISION NOTICERELEASENUMBERREV.

DATE OFRELEASE

7050-1D01

A

06/09/03

DESCRIPTION

Original release.

-iii-

INTRODUCTIONREVISION HISTORYRELEASE 7050-1D01
Original release.

Revision A (06/09/03)-iv-

INTRODUCTION

7050 – Change Language

mode

mode

enter

-v-

INTRODUCTION

SAFETY SUMMARY

The following are general safety precautions that are not related to any specificprocedures and do not appear elsewhere in this publication. These are recommended
precautions that personnel must understand and apply during equipment operation andmaintenance to ensure safety and health and protection of property.

KEEP AWAY FROM LIVE CIRCUITS

Operating personnel must at all times observe safety regulations. Do not replacecomponents or make adjustments inside the equipment with the voltage supply
connected. Under certain conditions, dangerous potentials may exist when the power
control is in the off position due to charges retained by capacitors. To avoid injuries,
always remove power from, discharge, and ground a circuit before touching it.

DO NOT SERVICE OR ADJUST ALONE

Do not attempt internal service or adjustment unless another person capable ofrendering aid and resuscitation is present.

RESUSCITATION

Personnel working with or near dangerous voltages shall be familiar with modern
methods of resuscitation. Such information may be obtained from your local American
Medical Association.

ELECTRO STATIC DISCHARGE SENSITIVE PARTSCAUTION: Electrostatic discharge sensitive (ESDS) is applied to low power, solid-stateparts which could be damaged or destroyed when exposed to discharges of static
electricity. Maintenance personnel are often not aware that an ESDS part has beendamaged or destroyed because electrostatic discharges at levels less than 4,000
volts cannot be seen, felt, or heard.

COMPRESSED GAS

Use of compressed gas can create an environment of propelled foreign matter. Pressure
system safety precautions apply to all ranges of pressure. Care must be taken during
testing to ensure that all pneumatic connections are properly and tightly made prior toapplying pressure. Personnel must wear eye protection to prevent injury.

PERSONAL PROTECTIVE EQUIPMENT

Wear eye protection approved for the materials and tools being used.

INERT GASES

Operation of pressure equipment may be accompanied by the discharge of inert gases tothe atmosphere. The result is a reduction of oxygen concentration. Therefore, it is strongly
suggested that exhaust gases not be trapped in the work area.

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INTRODUCTION

TABLE OF CONTENTSWARRANTY ............................................................................................................ -iiCOPYRIGHT NOTICE ............................................................................................ -iiiREVISION NOTICE ................................................................................................ -ivREVISION HISTORY................................................................................................ -vCHANGE LANGUAGE........................................................................................... -viSAFETY SUMMARY ................................................................................................ -viTABLE OF CONTENTS .......................................................................................... -viiSECTION 1.0: GENERAL INFORMATION
1.1
INTRODUCTION ................................................................................1-1
1.2
GENERAL INFORMATION ...................................................................1-1
1.3
FEATURES...........................................................................................1-1
1.4
STANDARD EQUIPMENT & OPTIONS ..................................................1-2
SECTION 2.0: THEORY OF OPERATION
2.1
INTRODUCTION ................................................................................2-1
2.2
POWER SUPPLY ..................................................................................2-1
2.3
ELECTRONICS MODULE .....................................................................2-2
2.3.1 BACK-PLANE BOARD ................................................................2-2
2.3.2 MICROPROCESSOR BOARD......................................................2-2
2.3.3 IEEE-488 INTERFACE ................................................................2-3
2.3.4 FRONT PANEL ..........................................................................2-3
2.4
PNEUMATICS MODULE.......................................................................2-3
2.4.1 MEASURE MODE PNEUMATICS.................................................2-5
2.4.1.1 Reference Port..............................................................2-5
2.4.1.1.1 Barometric Sensor...........................................2-5
2.4.1.2 Test Port ......................................................................2-6
2.5
TRANSDUCER MODULE ......................................................................2-6
2.5.1 QUARTZ BOURDON TUBE SENSOR (TRANSDUCER01) ..............2-6
2.5.2 SENSOR BOARD.......................................................................2-7
2.5.3 LINEARIZATION TERM...............................................................2-7
2.5.4 AUXILIARY SENSORS.................................................................2-8
2.5.4.1 Case Reference Vacuum Sensor ....................................2-8
2.6
SOFTWARE .....................................................................................2-8
2.6.1 SAFETY CONSIDERATIONS .......................................................2-8
2.6.1.1 Oven Control ..............................................................2-8
2.6.1.2 Pressure Reading and Correction ..................................2-9
SECTION 3.0: INSTALLATION
3.1
INTRODUCTION ................................................................................3-1
3.2
UNPACKING THE PPI ..........................................................................3-1
3.3
CAUTIONS .....................................................................................3-2
3.4
POWERING UP THE PPI.......................................................................3-2-vii-

INTRODUCTION

3.5

3.4.1 OBSERVING THE PPI’S FULL SCALE RATING ..............................3-2
PNEUMATIC CONNECTIONS .............................................................3-2
3.5.1 TEST PORT................................................................................3-2
3.5.2 REFERENCE PORT .....................................................................3-3

SECTION 4.0: LOCAL OPERATION
4.1
TUTORIAL.....................................................................................4-3
4.1.1 SELECTING LANGUAGE ...........................................................4-4
4.1.2 SELECTING MODE OF OPERATION ..........................................4-4
4.1.2.1 Simulated Absolute Instruments.....................................4-4
4.1.2.2 True Absolute with Vacuum Reference Option................4-5
4.2
MAIN MENU .....................................................................................4-5
4.3
MENU ................................................................................................4-5
4.3.1 MENU | SETUP .........................................................................4-6
4.3.1.1 Menu | Setup - Limits ...................................................4-6
4.3.1.1.1 High Limit ......................................................4-6
4.3.1.1.2 Low Limit........................................................4-7
4.3.1.1.3 Slew Limit .......................................................4-7
4.3.1.1.4 Access............................................................4-7
4.3.1.2 Menu | Setup - User ....................................................4-7
4.3.1.2.1 Gas Head Pressure Correction.........................4-7
4.3.1.2.2 Atmosphere....................................................4-8
4.3.1.2.3 Pressure Filter .................................................4-8
4.3.1.2.4 Changing the Number of Decimals..................4-8
4.3.1.2.5 Key Click ........................................................4-8
4.3.1.3 Menu | Setup - Units ....................................................4-9
4.3.1.4 Menu | Setup - Remote ..............................................4-10
4.3.1.4.1 GPIB Address................................................4-10
4.3.1.4.2 Protocol........................................................4-10
4.3.1.4.3 Serial Interface Set-Up...................................4-10
4.3.1.5 Menu | Setup - System ...............................................4-10
4.3.1.5.1 Date | Time..................................................4-11
4.3.1.5.2 Reset ............................................................4-11
4.3.2 MENU | CALIBRATE ................................................................4-11
4.3.2.1 Calibration Password .................................................4-12
4.3.2.2 Zeroing .....................................................................4-12
4.3.3 MENU | TEST .........................................................................4-13
4.3.4.1 Menu | Test - Self Test................................................4-13
4.3.4.2 Menu | Test - Remote Test ..........................................4-13
4.3.4.3 Menu | Test - Shop 1 .................................................4-14
4.3.4 MENU | DISPLAY ....................................................................4-14
4.3.4.1 Menu | Display - Blank ..............................................4-14
SECTION 5.0: REMOTE OPERATION
5.1
CAPABILITIES .....................................................................................5-1-viii-INTRODUCTION

5.2
5.3
5.4

5.5
5.6
5.7

5.8

5.1.1 IEEE-488 ..................................................................................5-1
5.1.2 RS-232 .....................................................................................5-1
REMOTE/LOCAL OPERATION .............................................................5-2
CONFIGURATION ..............................................................................5-2
DEVICE MESSAGES .............................................................................5-3
5.4.1 SCPI COMMAND FORMAT .......................................................5-3
5.4.2 SCPI RESPONSE FORMAT..........................................................5-3
5.4.3 ANSI/IEEE 488.2-1987 COMMAND SUMMARY .........................5-4
5.4.4 SCPI COMMAND SUMMARY.....................................................5-4
5.4.5 EXAMPLE SCPI COMMANDS .....................................................5-6
5.4.6 SCPI STATUS REGISTERS ...........................................................5-7
6005 INTERFACE PANEL EMULATION .................................................5-8
SERIAL OPERATION ............................................................................5-9
DRUCK DPI-510 EMULATION COMMAND SUMMARY .........................5-9
5.7.1 SUPPORTED COMMANDS ........................................................5-9
5.7.2 RESPONSE FORMATS..............................................................5-10
5.7.3 RESET CONDITIONS...............................................................5-10
5.7.4 KEYBOARD ENTRY ..................................................................5-10
5.7.5 NOTES ...................................................................................5-10
SAMPLE PROGRAMS .........................................................................5-11
5.8.1 SAMPLE PROGRAM 1 - 7050 GPIB (IEEE-488) - CONTROLSPRESSURE TO 20.000%FS .......................................................5-11

SECTION 6.0: MAINTENANCE
6.1
INTRODUCTION ................................................................................6-1
6.2
OBSERVING THE SOFTWARE VERSION NUMBER .................................6-1
6.3
PREVENTIVE MAINTENANCE ...............................................................6-1
6.3.1 INITIATING THE PPI'S SELF TEST ................................................6-1
6.3.2 MOISTURE FILTER .....................................................................6-2
6.3.3 PARTICLE FILTERS .....................................................................6-2
6.3.4 VACUUM PUMPS ......................................................................6-2
6.3.5 PROCESSOR BATTERY...............................................................6-3
6.4
CALIBRATION.....................................................................................6-3
6.4.1 CALIBRATION INSTRUCTIONS ..................................................6-3
6.4.1.1 Preparation..................................................................6-3
6.4.1.2 Storing the Coefficients.................................................6-6
6.4.2 VACUUM (NEGATIVE GAUGE) CALIBRATIONS ..........................6-7
6.4.3 RPT CALIBRATION - SIMULATED ABSOLUTE ..............................6-8
6.4.4 EDITING THE CALIBRATION COEFFICIENTS ..............................6-8
6.4.5 ZEROING .................................................................................6-9
6.4.5.1 Gauge and Vacuum (Negative Gauge) Instruments .....6-10
6.4.5.2 Absolute Instruments ..................................................6-11
6.4.5.3 RPT - Simulated Absolute Instruments ..........................6-12
6.5
SENSOR PHOTOCELL ZEROING .......................................................6-12
6.6
FAN OPERATION..............................................................................6-15-ix-

INTRODUCTION

6.7
6.8

SYSTEM SOFTWARE UPDATE PROCEDURE.........................................6-15
REPLACEMENT PARTS........................................................................6-16

SECTION 7.0: PREPARATION FOR STORAGE & SHIPMENT
7.1
DISCONNECTING THE PPI..................................................................7-1
7.2
PACKING INSTRUCTIONS...................................................................7-1
7.3
SHIPPING INSTRUCTIONS ..................................................................7-3
APPENDIX A: SUMMARY OF SPECIFICATIONS
A.1 ACCURACY ........................................................................................A-1
A.2 SPECIFICATIONS ................................................................................A-5
APPENDIX B: SUMMARY OF ERROR MESSAGES ................................................. B-1-x-

INTRODUCTION

LIST OF FIGURESFIGURE 2-1:
FIGURE 2-2A
FIGURE 2-2B
FIGURE 2-2C
FIGURE 2-3:
FIGURE 2-4:
FIGURE 2-5:
FIGURE 2-6:

PPI BLOCK DIAGRAM .......................................................................2-1
MODEL 7050 PPI GAUGE PNEUMATICS DIAGRAM ...........................2-4
MODEL 7050 PPI ABSOLUTE PNEUMATICS DIAGRAM .......................2-5
MODEL 7050 PPI ABSOLUTE PNEUMATICS DIAGRAM .......................2-5
PRESSURE CONTROL PRECISION MODE...........................................2-9
PRESSURE CONTROL FAST MODE ....................................................2-9
SHAFT/MAGNET SECTION ...............................................................2-7
PHOTOCELL/LIGHT SPOT ................................................................2-7

FIGURE 3-1:

MODEL 7050 BACK PANEL ..............................................................3-3

FIGURE 4-1:
FIGURE 4-2:

MODEL 7050 FRONT PANEL ............................................................4-1
MENU TREE......................................................................................4-2

FIGURE 6-4:
FIGURE 6-5:

VACUUM CALIBRATION ...................................................................6-7
PHOTOCELL LOCATION ..................................................................6-4

FIGURE 7-1:

PACKAGING THE PPI........................................................................7-3

LIST OF TABLESTABLE 1-1:

OPTIONS LIST FOR THE MODEL 7050 ................................................1-3

TABLE 2-1:
TABLE 2-2:

CONVERSION FACTORS.....................................................................2-3
SOLENOID VALVE STATES...................................................................2-6

TABLE 3-1:

GENERAL SPECIFICATIONS: GENERAL PARAMETERS ............................3-1

TABLE 6-1:
TABLE 6-2:

ELECTRONICS SELF TEST ....................................................................6-2
PNEUMATICS SELF TEST......................................................................6-2

TABLE A-1:

PERFORMANCE SPECIFICATIONS........................................................A-6-xi-

INTRODUCTION

SECTION 1.0
GENERAL INFORMATION
1.1 INTRODUCTION
This manual contains operation and routine and preventive maintenance instructions for
the Model 7050 Precision Pressure Indicator (PPI) manufactured by Ruska Instrument
Corporation, Houston, Texas. This section of the manual provides general information
about the PPI and presents its features and options.
1.2 GENERAL INFORMATIONThe Ruska Model 7050 PPI uses force-balanced, fused-quartz Bourdon tube technology
to provide the precise measurement of pressure.
In Measure mode, the PPI measures pressure. Typically, Measure mode applications arefound in research laboratories, wind tunnel testing, power plant testing, and bubbler tankvolume accountancy systems. It is also used to monitor barometric pressures, vacuum
systems, and differential pressure devices.
1.3 FEATURES
The following features are available on all Model 7050 PPI’s.
Fused-Quartz Bourdon Tube Technology: (5 - 2500 psi full scale ranges) Ruska’sforce-balanced, fused-quartz Bourdon tube sensor makes use of the stability, highelasticity, low hysteresis, and excellent fatigue strength of fused quartz. This time-proventechnology eliminates the need for gear trains, bearings, shafts, and other moving parts
that can wear out or introduce hysteresis or deadband into the process.
Mercury-Free: All components in the PPI are mercury-free.
NIST Traceability: All PPI’s are calibrated per ANSI/NCSL Z-540-1-1994 using Ruska
deadweight gauges that are directly traceable to the National Institute of Standards andTechnology (NIST).
Universal Power Supply: The PPI’s universal power supply accepts AC voltages
between 90 and 260 volts, and DC voltages between 100 and 370 volts. To“reconfigure” the PPI for use in another country, the user simply changes the power cord.
Friendly Display: The PPI’s color active matrix TFT display combines a bright, low-glare
readout with a wide viewing angle. During normal operation, the measured pressure iseasily visible from a distance of 10 feet (3 meters).
Adjustable Pressure Display: The pressure display may be adjusted to show one
decimal greater than or less than the default resolution.
Ease of Operation: An intuitive, menu-driven interface makes the PPI easy to use.
Frequently used selections such as the units of measure are restored to memory eachtime the PPI powers up.
Modular Design: The sensing element, pneumatics, electronics, and user interface are
separated into modules, making maintenance faster and easier.

1-1

INTRODUCTION

Attractive Desktop Packaging: A sturdy aluminum case houses all of the PPI’s
pneumatics, electronics, and user controls. With the optional rack mount kit, thisstandard 19" EIA chassis fits easily into a rack mount system.
Power On Self Test: Upon power-up, the PPI quickly tests its hardware and software.
After the PPI completes this test, the user can select more extensive self-tests for thepneumatics and electronics.
Ease of Calibration: Calibration may be performed either remotely or entirely from thefront panel. No disassembly is required, and there are no potentiometers to tune. On
single sensor units, only a three-point calibration is required to fully characterize theinstrument. On instruments that integrate multiple ranges such as the 7050i and
7050LP, additional calibration points are required.
Automatic Zero Adjust: At the user’s request, the PPI’s software automatically performs
the zero adjustment, with no potentiometers to tune.
Automatic Head Correction: The PPI automatically corrects for head pressure between
the PPI and the device under test (DUT), taking into account the density of the test gas;e.g., air or nitrogen.
Choice of Medium: Although the PPI is not sensitive to the type of gas used within thesystem, the user can select either instrumentation air or nitrogen, allowing the PPI toautomatically make pressure head corrections.
Choice of Display Units: Standard units include inHg at 0°C and 60°F, kiloPascals,
bars, psi, inH2O at 4°C, 20°C, and 25°C, kilograms per square centimeter, mmHg,
cmHg at 0°C, and cmH2O at 4°C. Altitude and airspeed units include feet, meters, knots,
and kilometers per hour. In addition to these predefined units, four user-defined units
are programmable.
Communications Interface: The PPI includes standard RS-232 serial and IEEE-488
interfaces. The user’s computer communicates with the PPI through the Standard
Commands for Programmable Instruments (SCPI) protocol. The 7050 shares the same
protocol as the Ruska 7010, 7215, 7215i and 7215xi, therefore, it can operate fromsoftware written for any of these products. The PPI can also be configured to accept
existing software written for the Ruska Series 6000 Digital Pressure Gauge/Controller or
the Druck model 510.
1.4 STANDARD EQUIPMENT & OPTIONS
A standard PPI includes this manual and a power cord. Although the standard PPI is fully
functional with just these items and the appropriate pressure and vacuum supplies, thefollowing options are also available.
NVLAP Accredited Calibrations - Ruska received formal accreditation from the
National Voluntary Laboratory Accreditation Program (NVLAP) which is administrated by
the National Institute of Standards and Technology (NIST). NVLAP has assigned Ruska
laboratory code 200491-0 to indicate that our accredited calibration services are incompliance with all relevant requirements of ISO/IEC 17025:1999 and ISO 9002:1994.
Ruska's calibration laboratory can provide an optional accredited pressure calibration.
The NVLAP calibration certifications are optional and must be requested at time of order.
1-2

INTRODUCTION

Rack Mount Kit: This 6.969" kit meets ANSI/EIA requirements for a 4U, 19" rack mountkit.
Additional Power Cords: Additional power cords are available for most countries.
All options are summarized in Table 1-1. To order these items, please contact Ruska
Instrument Sales in the U.S. at (713) 975-0547.
TABLE 1-1
OPTIONS LIST FOR THE MODEL 7050 PPI
OptionRuska Instrument Corp.
Part Number (RIC #)LabView Driver (National Instruments)
Rack Mount Kit - Cabinets 18-24 inches deep
Vacuum Pump
115 VAC 50/60 Hz
230 VAC 50/60 Hz
Power Cord - USA, Canada, Central Europe
Power Cord - India, Japan, Israel
Power Cord - Australia/New Zealand

Downloadable from World Wide Web
7250-903
99877-800
99877-860
16-81, 16-81, 16-86
16-96, 16-93, 16-97
16-95

1-3

INTRODUCTIONNOTES

1-4

INTRODUCTION

SECTION 2.0
THEORY OF OPERATION
2.1 INTRODUCTION
The PPI’s power supply, electronics, pneumatics, and sensor combine to form a complete,stand–alone instrument. This section of the manual describes the PPI’s component
modules (Figure 2–1) and provides a general discussion of each.

Primary Transducer Module
SENSOR

CASE

Section
2.6.1

TUBE

POWER
SUPPLYBACKPLANE
BOARD

Section
2.2

Section 2.3.1

Photo
SensorSENSOR
BOARD
Section
2.6.2

AC
POWER

FRONT
PANEL

IEEE
CARD

MICROPROCESSOR
BOARD

Section
2.2

Section
2.3.5

Section
2.3.4

Section 2.3.2
RS -232

Electronic Module
IEEE-488

FIGURE 2-1
PPI BLOCK DIAGRAM
2.2 POWER SUPPLYThe PPI’s universal power supply accepts AC voltages from 90 to 260 volts at 47-63 Hz.
and DC voltages from 100 to 370 volts. This quad–output supply produces +5 VDC,+/-12 VDC, and 24 VDC which are distributed to the Control and Backplane Boards.

2-1

THEORY OF OPERATION

2.3

ELECTRONICS MODULE

2.3.1 BACK-PLANE BOARD
The Back-plane Board is used to interconnect all of the plug-in electronic boards anddistribute power. The Microprocessor Board, the Digital Control Board, and the IEEE–
488 Interface all plug into the Back-plane Board. The Front Panel communicates with theMicroprocessor Board via cables.
The Sensor Board communicates with theMicroprocessor board through an internal RS-485 serial communication bus.
2.3.2 MICROPROCESSOR BOARD
All of the PPI’s software resides in nonvolatile, programmable, read–only memory (FlashEPROM) on the Microprocessor Board, which plugs directly into the Back-plane Board.
This software contains all of the instructions that operate the PPI, as well as theconversion factors that the PPI uses to translate the internal pressure unit-of measure ofkPa into the units selected by the user. These factors are given in Table 2–1.
Data that is subject to change after the PPI leaves the factory are held in electricallyerasable, programmable, read–only memory (EEPROM). This includes the current unitsof measure, the coefficients from the zeroing process, the current pressure medium,
calibration coefficients, and the conversion factors for the four user–defined units ofmeasure.
When the PPI powers up, its software is loaded into random access memory (RAM), also
on the Microprocessor Board. At the same time, the values stored in EEPROM Board arerestored to memory.
Another important component on the Microprocessor Board is the lithium battery. The
battery continuously updates the PPI’s date and time, even when the unit is powered
down. This battery has a varying life. If the instrument is left on 24 hours a day, it may
last 5 to 10 years. If the instrument is stored, it may only last one year.
The Microprocessor Board also supports the RS–232 serial interface that allows the user’s
computer to communicate with the PPI.

2-2

THEORY OF OPERATIONTABLE 2–1
CONVERSION FACTORS
Unless specified otherwise, conversion factors are based on ANSI 268–1982.
SymbolDescription

Conversion Factor

InHg

inches of mercury (0 °C)= kPa x 0.2952998

InHg

inches of mercury (60 °F)= kPa x 0.296134

KPa

KiloPascals= kPa x 1.0

Bar

Bars

= kPa x 0.01

Psi

pounds per square inch

= kPa x 0.1450377

cmH20

Centimeters of water (4 °C)= kPa x 10.19744

inH20

inches of water (4 °C)= kPa x 4.014742

kg/cm2

kilograms per square centimeter= kPa x 0.0101972

mmHg

Millimeters of mercury (0 °C)= kPa x 7.500605

cmHg

Centimeters of mercury (0 °C)= kPa x 0.7500605

knots

indicated airspeed

per NASA TN D–822

km/hr

kilometers per hour

= knots x 1.852

Feet

feet of altitude

per MIL–STD–859A

metersmeters of altitude

per MIL–STD–859A

User1

user defined= kPa x user definedUser2

user defined= kPa x user definedPauser defined (Pascals)= kPa x 1000.0hPa

user defined (hectoPascals)= kPa x 10.0

%FS

percent of full scale

2.3.3 IEEE–488 INTERFACE
The PPI’s IEEE–488 (GPIB) interface card, which plugs directly into the Back-plane Board,
provides the PPI with an IEEE–488 interface. This interface allows the user to automate
the measurement and control processes.
2.3.4 FRONT PANEL
The Front Panel contains the active matrix TFT color display, rotary knob and rubberized
keys used to operate the PPI.
2.4 PNEUMATICS MODULE
The PPI's Pneumatics Module varies depending on whether the PPI is a Gauge mode or
Absolute mode instrument. Gauge mode PPI's reference their measurements to
2-3

THEORY OF OPERATION

atmospheric pressure, whereas Absolute mode PPI measurements are made with respect
to sealed vacuum.
A Simulated Absolute mode PPI has a barometric sensor in addition to a gauge Bourdon
tube sensor. The PPI adds the barometric reading to the Bourdon tube reading to obtaina Simulated Absolute value. It can operate as a Gauge mode instrument if the user
selects to not add the reference pressure.
The 7050 can also be supplied with an optional vacuum reference sensor. In thisconfiguration, the 7050 can operate in the absolute mode by connecting a high capacity
vacuum pump to the reference pump of the 7050 and evacuating the reference.
Therefore, both the barometric and the vacuum reference option allow the 7050 tooperate in the absolute mode in addition to gauge mode. The difference between these
two options are that the barometric option would not require an external vacuum pump
to measure absolute pressures. The vacuum reference option would provide a moreaccurate absolute measurement, however, it would require and external vacuum pumpevacuating the reference port to measure absolute pressures.
The valves, filters, and transducers that make up the pneumatics module of a Gauge
mode (or Simulated Absolute) PPI are shown in Figures 2-2a. The schematics for theAbsolute mode PPI is shown in Figure 2-2b.
REFERENCE
PORT

BAROMETRICREFERENCESENSOR(SIMULATEDABSOLUTEOPTION)

TEST
PORT

ZERO

PRIMARY SENSOROPTIONAL
VACUUM SENSOR

FIGURE 2–2A
MODEL 7050 PPI GAUGE PNEUMATICS DIAGRAM
5 to 2500 psig (34 kPa to 17.2 MPa) Full Scale Ranges
2-4

THEORY OF OPERATIONREFERENCE
PORT

TEST
PORT

ZERO

PRIMARY SENSOR

VACUUM SENSOR

FIGURE 2–2B
MODEL 7050 PPI ABSOLUTE PNEUMATICS DIAGRAM TO 50 PSIA (340 kPa) FS
2.4.1 MEASURE MODE PNEUMATICS
Figures 2–2A through 2–2C summarizes the Pneumatics of the PPI.
2.4.1.1 Reference Port
For gauge measurements, the Reference Port is left open to atmosphere.
The Reference Port is isolated from the Test Port by a solenoid valve that is closed during
the PPI’s Measure mode. When the user commands the PPI to perform the zeroingprocess, the solenoid automatically opens, and the pressures on the Reference Port andTest Port become equal.
The Reference Port is protected by a relief valve.
2.4.1.1.1 Barometric Sensor
For all Simulated Absolute instruments, the Reference Port is monitored by a precision
barometric sensor (Figure 2-2A). This sensor provides the barometric offset that allows
the Gauge mode PPI to function in a simulated Absolute system.
2.4.1.1.2 For instruments that have the vacuum reference option, a vacuum gauge isconnected to the reference port. The operator can connect a vacuum pump to thereference port of the 7050 and evacuate its reference. The vacuum sensor is then used
to zero the 7050 in the absolute mode and to track any vacuum changes that occur inthe reference ports.
2-5

THEORY OF OPERATION

2.4.1.2 Test Port
The Test Port connects the DUT to the Pneumatics Module.
The Test Port is protected by a relief valve.
2.5

TRANSDUCER MODULE

2.5.1 QUARTZ BOURDON TUBE SENSOR (TRANSDUCER01)
The quartz Bourdon tube sensor is mounted in a machined aluminum housing. The
sensor consists of a helical quartz tube with a mirror affixed to one end, as shown in
Figure 2-5.
A rigid beam is attached transverse to the axis of the helical tube. Attached to both endsof this beam are electromagnetic coils. Mounted beneath the coils are permanent
magnets. A lamp assembly directs light through a quartz or sapphire window onto themirror affixed to the helical tube, as shown in Figure 2–6. The mirror reflects the lightback through the window and strikes two matching photodiodes. When there is zeropressure differential across the helical tube, the photodiode assembly is mechanicallyadjusted so that the light spot is centered between each photocell. In this “zero position,”the outputs of the two photodiodes provide energy used to maintain the quartz assemblyin its zero position; thus, a force balance is created.
As pressure is applied in the helical tube, the entire apparatus attempts to rotate. This
causes the mirror to move the reflected light spot to shine more on one photodiode thanthe other. The Sensor Board (see Section 2.5.2) then responds by changing the current to
the electromagnetic coils that, through interaction with the permanent magnets, force thehelical tube to return to its zero position. The amount of current required to do this is
proportional to the pressure applied across the helical tube. Thus, the pressure isdetermined by the amount of current required to return the helical tube to its zero
position.
L AB

TE M

SOLU

On Absolute Models, the process is similar, except that the Bourdon tube ispermanently evacuated to less than 0.1 mtorr and sealed at the factory, andthe test pressure is applied to the sensor case. With this configuration, all test
pressures are measured with respect to vacuum.

2-6

THEORY OF OPERATIONODEFIGURE 2–5
SHAFT/MAGNET SECTION

FIGURE 2–6
PHOTOCELL/LIGHT SPOT
2.5.2 SENSOR BOARD
A temperature sensor and the quartz Bourdon tube pressure sensor are monitored by the
Sensor Board. The Sensor board is also used to control and maintain the sensor housing
at 50°C.
2.5.3 LINEARIZATION TERM
As described in the previous section, the relationship between the pressure being
measured and the current required to keep the quartz Bourdon tube in its zero position is
the main principle behind the operation of the PPI’s sensing element.
Ideally this pressure-current relationship would be a linear equation of the form

I = kP,
2-7

THEORY OF OPERATION

where I is current, k is a constant of proportionality, and P is pressure. However, due tocertain mechanical characteristics of the helical tube and its supporting structure, thispressure-current relationship is slightly nonlinear. The nonlinear portion of this pressurecurrent relationship closely follows the form of a second order polynomial, or
I = aP 2 + bP + c,
where again P is pressure and a, b, and c are coefficients generated during thecalibration procedure as discussed below.
When the user performs a three-point calibration, the PPI’s software creates the threecoefficients based on the user’s zero, mid-point, and full-scale adjustments. From thenon, the nonlinear term given above is subtracted from the total pressure-current curve toachieve the desired linear pressure-current relationship.
On the 7050i and 7050LP, multiple quartz sensor ranges are used in order to provide
the percent of reading specification. In these instruments, a total of three points per
range with one point shared between two ranges is required. Therefore, for the 7050i, a
5 point calibration is performed and for the 7050LP, a 9 point calibration is performed to
fully characterize the Ruska quartz sensors.
2.5.4 AUXILIARY SENSORS
Auxiliary sensors are sensors such as the oven temperature sensor. These are reference
sensors aligned at the factory and are utilized by the firmware.
2.5.4.1 Case Reference Vacuum Sensor
The case reference vacuum sensor is an optional sensor. The user needs this sensor tozero an Absolute PPI. Please note that the uncertainty of the vacuum sensor used to zero
the PPI must be considered in the overall uncertainty analysis of the PPI.
2.6 SOFTWARE
The PPI is a digital, software-based instrument.
2.6.1

SOFTWARE SAFETY CONTROLS

2.6.1.1 Oven Control
The oven temperature is controlled via a pulse-width modulated signal. The time theheater is on can be varied from 0 to 100%. The pulse-width at startup is initialized to theprevious value which was stored in battery-backed CMOS RAM.
The oven control is a PID controller updated approximately every 7 seconds. The sensor
readings are accessed by pressing MENU | DISPLAY. With an exception of the 3000
psi (20.7 MPa) version 7050, the high accuracy quartz sensor is housed in a temperature
controlled oven. There is a 3 hour warm-up time required prior to the PPI operating at its
optimum precision. The user can verify when the instrument is thermally stable byviewing the MENU | DISPLAY screen and verifying that the temperature is at 50o C. In
addition to the temperature, this screen will show the duty cycle of the oven.

2-8

THEORY OF OPERATION

When operating the system in either a very cold or hot environment, if the oven in unable
to maintain the temperature of the internal oven, the PPI will generate an Oven Control
Failure error messages. The operator can review the temperature and duty cycle of theoven by pressing the MENU | DISPLAY keys. The unit must be have been warmed up
for a minimum of 3 hours prior to determining the condition of the oven temperature
control. The temperature of the sensor should be controlled to 50o C. The Duty Cycle
indicates the amount of time (in units of percentage) that the oven control is turned on inorder to maintain the oven at the proper set-point of 50o C. A unit that is operating
properly, after it has fully warmed up, should indicate a sensor temperature of 50o C anda duty cycle between 10 to 90%.
If operating the instrument in a very cold environment and the oven duty cycle is at ahigh percentage (>90%) you will need to turn the fan off. If you are operating in a warm
environment or when multiple systems are housed in consoles without adequate
ventilation, the system may become too hot and generate the oven control failure error
message. If operating the instrument in a warm environment and the oven duty cycle is
at a low percentage (>10%) you will need to turn the fan on. See Section 6.6 for fan
operation.
When the operator changes the status of the fan, it will remain in that condition until theoperator changes the setting.

MENU | DISPLY - MENU
2.6.1.2 Pressure Reading and Correction
The sensor’s analog output is processed by an analog-to-digital circuit that results in an
output referred to as counts. This output is corrected for the applied effects listed below.
The counts are linearized and the resulting pressure value is corrected for the variationsin head pressure, vacuum, case effect, and oven temperature effects.
The following equations are used by the control algorithm to adjust and correct thepressure signal.

2-9

THEORY OF OPERATION

Zero Coefficients
CsH

Zero correction for High FSR (Full-Scale Resistors) Value is in counts(7,381,975 = full scale of current sensor).

CsL

Zero correction for Low FSR. Value is in counts (7,381,975 = full scale of
low FSR)

HsZ

Hardware zero correction. (0 to 4095, center is 2048).

SsZ

Zero corrections scaling factor. Ratio of High FSR to Low FSR. Used only
when Case Effect Coefficient or Oven Temperature Coefficient are nonzero.

s=0 for high range sensor, s=1 for low range sensor.
Range Coefficients
KnF

0=Range Unused
4=Valid High FSR Range
5=Valid Low FSR Range

Kn0, Kn1, Kn2

Calibration constants for range
KK

B = 248n 2 ∗ A2 + 224n1 ∗ A + Kn0
Where A is the zero corrected counts (7,381,975 = full scale of current
range) and B is the calibrated counts (7,381,975 = full scale of current
sensor)
KnH

Zero corrected counts for upper limit of range. When the zero corrected
counts from the A/D exceed this value the next higher range will be used (ifpossible). (7,381,975 = full scale of current range)

KnL

Zero corrected counts for lower limit of range. When the zero corrected
counts from the A/D are below this value the next lower range will be used
(if possible). (7,381,975 = full scale of current range)n=Range number (1 - 4 for high range sensor, 5 - 8 for low range sensor)

2-10

THEORY OF OPERATIONSECTION 3.0
INSTALLATION
3.1 INTRODUCTION
This section of the manual discusses initial installation for the Model 7050 PPI. Installing
the PPI involves connecting the supply and test pressure tubing, powering up the unit, andconfiguring the system through the front panel.
3.2 UNPACKING THE PPI
Carefully unpack all components, checking for obvious signs of damage. The shipment
contains the following items:
1. Model 7050 or 7050i PPI
2. power cord,
3. user’s manual,
4. calibration report,
5. user-specified instrument options.
If necessary, report any shipping damage to the freight agency. Remove all shipping andpacking materials (including the shipping plugs) from all components. If possible, savethe packing materials for future shipping needs.
Finally, install the PPI in a location that meets the requirements listed in Table 3-1.
NOTE: The PPI should be handled in such a way as to minimize mechanical shocks orvibration during installation or use. It should be mounted on a rigid bench or in a
sturdy 19" rack. Although the zeroing process will compensate for a slightly
unlevel mounting, the PPI should be mounted to within 5° of level.
TABLE 3-1
GENERAL SPECIFICATIONS: GENERAL PARAMETERS
Parameter
Operating Humidity
Storage Humidity
Operating Temperature
Storage Temperature
Electrical PowerPower Consumption
Warm-up Period

Value
5–95%RH, noncondensingNone*
18 – 36°C-20 to 70°C
90–260 VAC
150 W< 3 hrs

Model
all
all
all
all
all
all
all

*If there is any condensation when storing the PPI, it must be thoroughly dried before
power is applied. It is also recommended to connect the reference port to the test port
and evacuating these simultaneously to remove any moisture from the sensor.

3-1

INSTALLATION

3.3 CAUTIONS
The following cautions should be heeded at all times to ensure safe operation of the PPI.
1. Never operate the PPI with the cover removed. The power supply has internal
voltages near 400 volts.
2. Never apply more than 120% of the PPI’s full scale as a pressure supply. Pressure
supply must be regulated and meet all criteria as stated in Appendix A of thismanual.
3. Never apply more than 110% of the PPI’s full scale to the test port. Never try tocontrol while a pressure source is connected to the test port.
4. Do not expose the instrument to thermal and mechanical shock, or vibration. This
may affect performance and require rezeroing.
5. See the safety summary in the introduction.
3.4 POWERING UP THE PPIFirst, plug the power cord supplied with the PPI into the power connector on the PPI’s
back panel.
CAUTION: Grounding for the PPI is provided through the power cord.
Next, plug the power cord into a receptacle rated for any AC voltage between 90 and
260 volts. If a different power cord is necessary for your receptacle, consult Table 1-1 foravailable power cords.
Finally, turn on the PPI by toggling the power switch on the back panel. When the
MEASURE screen appears on the display, the front panel will be fully operational.
3.4.1 OBSERVING THE PPI’S FULL SCALE RATING
To observe the PPI’s full scale rating,
1. Press [PREVIOUS] until the main menu appears.
2. Select MENU | CALIBRATE The PPI’s full scale pressure rating (FS) will appear
on the screen (in the currently selected units of measure).
3. To return to the main menu, press [PREVIOUS].
3.5 PNEUMATIC CONNECTIONS
Pneumatic connection to the PPI is straightforward. The following sections discuss each
port. All ports are ¼-inch NPT pipe fittings. See Figure 3-1. Remove all plastic shippingplugs from the back panel pneumatic ports.
3.5.1 TEST PORTThe device(s) under test is connected to the test port. Excessive leaks in the test volume
will cause measurement errors in the device under test. Tubing connected from the test
port to the load volume should have an internal diameter greater than 1/8 inches (3mm). Tubing should be shorter than 15 feet (5 meters) when minimum diameter tubing
is used.
3-2

INSTALLATION

3.5.2 REFERENCE PORTThe reference port is open to atmosphere for gauge measurements or it can beconnected to the Reference Port of the Device Under Test. For true absolute only systems
or systems with the vacuum reference option, a vacuum pump capable of producing avacuum level of 200 mTorr or less at the sensor reference port is required (used to zero
the sensor).

POWER
85-265 VAC
50/60 HZ
150VA

SUPPLY EXHAUST

TEST

REF

NOTICE:FAN IS NORMALLY OFF.
SEE USER'S MANUAL TO
TURN ON.

FIGURE 3-1
MODEL 7050 BACK PANEL

3-3

INSTALLATIONTHIS PAGE INTENTIONALLY LEFT BLANK

3-4

INSTALLATIONSECTION 4.0
LOCAL OPERATIONThis section of the manual describes operation of the PPI using the front panel. The local
interface (front panel) consists of a color TFT display, a rotary knob and a set of keys.
The display shows the system status and menu options. The keys are grouped according
to function.
7050

FIGURE 4-1
MODEL 7050 FRONT PANEL
Numeric Keypad: This includes the number keys, the decimal point [.], and the change
sign key [-]. The [UNITS] key changes between units of measure, [MODE] changes
between modes of operation such as gauge and absolute, [MEASURE] is used to place
the unit into measure mode. [CLEAR] key will clear the numeric entry field. The[ENTER] key accepts the entered number or confirms a command.
Function Keys: These are the six keys that run vertically beside the display. The labelshown in the display beside each key identifies their function. These functions will change
based on which screen you are operating. For ease of communication, throughout the
manual we refer to these keys as [F1] through [F6]. We consider the top key to be F1
and the bottom F6.
Rotary knob: The rotary knob select a field for editing.
CANCEL, PREVIOUS: These keys are used to stop, undo, or exit the current operation.
The [CANCEL] key returns all edited fields on the current entry screen to their originalvalues. It also stops the current program sequence or calibration process. The[PREVIOUS] key exits the current menu and returns to the previous menu.
Figure 4-2 is a menu tree showing the relationship between all the menus in the system.
Refer to it for selections available under the menu. To move to a lower menu, press thefunction key with the correct label. To move towards the main menu, press the[PREVIOUS] key.

4-1

LOCAL OPERATION

Enter Menu State

Menu

Enter Setup Menu

Setup
LimitsSet high, low & slew limits, control mode, control band andaccess code

User

Set step size, head correction, filter and display digits

Units

Define user-defined units of measure

RemoteSet baud, parity, data bits, stop bits, GPIB address

SystemSet date and time, reset machine, view software version
Enter calibrate menu

Cal.

Zero

Zero Sensor
Enter Test menu

Test

Self

Perform self test

RemoteDisplay remote status

Shop1

Display solenoid valve status
Display transducer values

Disp.

Blank

Screen Saver

FIGURE 4-2
MENU TREE

4-2

LOCAL OPERATION

4.1 TUTORIAL
To begin the tutorial, first verify that the PPI is powered-up and that the pneumaticconnections have been completed. The PPI should display a screen similar to the one
shown below. (The right hand side of the display should show the options). At power up,
there may be errors relating to the default settings. If an error message is displayed in
red at the bottom of the screen, press [F6], then press [PREVIOUS]. If multiple errors
exist, you will need to press the [F6] key multiple times to clear all of the errors.

MAIN MENUThis is the Main Menu. It is at the top level of the menu tree (see Figure 4.2) and all
descriptions in this manual start from this point. The double sized numbers in the top
center of the display shows the current measured pressure (0.00 psi diff). The right sideof the screen shows a bar graph displaying the current pressure relative to a userconfigurable full-scale value. The highlighted label on the right hand side of the screen
displays the current assignments of the function keys [F1] through [F6] that are locatedbeside the display.
Step 1. Change the pressure units. The units are changed by selecting the UNITS key
on the keypad.

UNITS - MENU

4-3

LOCAL OPERATION

Step 2. Use the rotary knob located to the right of the display to move the highlight bar
to the desired unit. Note, the highlighted curser initially shows the current unitof measure. When the rotary knob is moved, the current unit remains
highlighted in a gray color, and the new unit is highlighted in a light blue
color.
Step 3. When the unit desired is highlighted, press the [ENTER] key on the far rightside of the front panel, under the numeric keypad. The display will return to
the MAIN screen with the current units.
4.1.1 SELECTING LANGUAGE
The 7050 PPI can operate in a variety of different languages. To select a different
language, press the Mode key two times [MODE], [MODE]. The current language will
be highlighted. Use the rotary knob to highlight a new language and hit the [ENTER]
key to select that language.
4.1.2 SELECTING MODE OF OPERATIONThe 7050 PPI is offered in three different modes. These are gauge only, absolute only,
simulated absolute which operates in both gauge and absolute modes. Using abarometric reference, or true absolute using the vacuum reference option which allows
both gauge and absolute modes.
4.1.2.1 Simulated Absolute Instruments
This 7050 PPI is a Gauge and Vacuum (Negative Gauge) instrument with a barometricreference sensor. The summation of the pressure reading from the measurement sensor
in the 7050 and the pressure reading from the barometric sensor provides for the"simulated absolute" pressure display. To change mode, from the keypad, press Mode,then select either Absolute [F1] or Gauge [F2] or Tare [F3]. Please note that theavailable selection may vary from unit to unit. For instance, on a permanent absolute
instrument, the “Gauge” option would not be available but the simulated gauge is, via
the Tare function.

MODE - MENU

4-4

LOCAL OPERATION

4.1.2.2 True Absolute with Vacuum Reference Option
This 7050 PPI is a gauge (and optionally negative gauge) mode instrument which also
has a vacuum reference sensor connected to internal reference of the primary sensor. An
external vacuum pump can be used to evacuate the reference port of the 7050. The
vacuum sensor is then used to zero the 7050 in the absolute mode and to track any
variations that occur to the vacuum when operating in the absolute mode.
4.2 MAIN MENUThe Main Menu displays the measured pressure in double-sized numbers. Below thepressure reading is the current unit of measure and mode (Gauge, Differential or
Absolute). The Main Menu can always be reached by repeatedly pressing [PREVIOUS].
The model 7050 is designed such that all of the commonly used functions are accessible
by a direct key on the key pad or from a top level function key. Less commonly used setup type functions are accessible through the menu function key.

MAIN MENU
4.3 MENU
The menu key is used to access the less commonly accessed configuration type functions.
This accesses the Setup, Calibration, Program, Test and Display functions.

MENU
4-5

LOCAL OPERATION

4.3.1 MENU | SETUP
Setup is used to configure the system. It includes setting all of the limits, user parameters,
user-defined units of measure, remote interface and system setup.

MENU | SETUP – MENU
4.3.1.1 Menu | Setup – Limits
The Menu | Setup | Limits menu is used to setup all of the limits in the system. The
pressure limits can be used to protect the device-under-test (DUT) from overpressure.

MENU | SETUP | LIMITS - MENU
4.3.1.1.1 High Limit – User defined Maximum pressure limit. This is often set just overthe full-scale pressure of the device under test (DUT) in order to protect the DUT. The PPI
will then prevent the pressure from exceeding the high limit. If the user enters a value
greater than the user defined limit, the unit will not accept the value and it will generate
an error code informing the user that they have entered a set-point that is greater thanthe high pressure limit. In control mode, if for any reason the pressure exceeds the user
defined limit, it will change into the measure mode and again display an error message
to the operator informing them of the error that occurred.
4-6

LOCAL OPERATION

This value can be edited using the rotary knob to highlight the High Limit. Then enter the
new value using the keypad. This will show up in the scratch pad on the lower portion of
the screen. Press the Enter key and the value for the high limit will be updated to thevalue that was typed into the scratchpad.
4.3.1.1.2 Low Limit – User defined Minimum pressure limit. This is the same as thehigh limit except it is to protect the DUT from low pressure limits.
4.3.1.1.3 Slew Limit – The slew limit is used by the system to assure that the slew rate is
not exceeded. If the slew rate is exceeded, the PPI will change from the control mode to
the measure mode and it will generate an error message to the operator.
4.3.1.1.4 Access – The test access password allows the user to protect access to PPI
configuration and programs. If the test access password is set to any number other thanzero (factory default), it is required before the user is allowed to change the limits, control
parameters or programs.
IMPORTANT: It is recommended that the access password be recorded and filed in asecure location.
4.3.1.2 Menu | Setup – User
The Menu | Setup | User menu is used to setup all of the user specific configurations.
This includes setting the control step size, range of bar-graph, pressure gas head, display
pressure filter, display resolution digits, and audible key click.

Menu | Setup | User - Menu
4.3.1.2.1 Gas Head Pressure Correction - The term “head height” refers to thevertical distance between the sensing element in the device under test and the PPI’spressure reference plane. Once the user inputs the head height and selects air or
nitrogen, the PPI automatically corrects for head pressure.
1. The Pressure Reference Line on the PPI is defined as the bottom of the color
display where the display and the front panel join. This provides the reference
plane against which the device under test (DUT) pressure is measured.
4-7

LOCAL OPERATION

2. Determine the vertical distance between the PPI Pressure Reference Line and thereference plane of the device under test.
3. Press the Unit key found in the keypad and press in/mm [F1] to select either
inches (in) or millimeters (mm) for the head height entry.
4. The head height is set from the Setup | User | Menu. From the Main Menu(press [PREVIOUS] until the Main Menu appears), press Menu [F6], then Setup[F2], and then User [F2].
5. Press Medium [F3] to select either “Air” or “Nitrogen.” The selected units will behighlighted.
6. Press Position [F4] to select if the position of the Device Under Test is either“Above” or “Below” the 7050. The selected units will be highlighted and appear
in the Gas Head description.
7. Use the rotary knob to highlight the label “Gas Head.”
8. Use the numeric keypad to enter the height in the selected unit.
9. Press [ENTER] to accept the entry.
4.3.1.2.2 Atmosphere – The nominal barometric pressure value for the location that
the PPI is utilized should be entered for atmosphere. On gauge mode instruments, thisnumber is used to calculate the density of the test port pressure medium and to correct
for head pressure variances between the reference port of the PPI and the DUT.
4.3.1.2.3 Pressure Filter – is used to adjust the degree to which the front display
pressure value is filtered. A value of four (4), is the default value. As the value increases,
the filtering level increases, however, the display update rate reduces. Typical filter
values would range between 1 to 10.
4.3.1.2.4 Changing the Number of Decimals – Each unit has a default number ofdecimal places used for pressure display. This may be adjusted up or down by one
decimal place.
1. The decimal digits are set from the Setup | User | Menu. From the Main Menu(press [PREVIOUS] until the Main Menu appears), press Menu [F6], then Setup[F2], and then User [F2].
2. Turn the rotary knob until the label “Display digits” is highlighted.
3. Turn the rotary knob further until the desired number of digits from the default
resolution is highlighted (-1, 0, +1), and then press the [ENTER] key to select.
4.3.1.2.5 Key Click – The PPI can be configured to emit a “clicking” sound each time akey is pressed.
1. The key “click” is set from the Setup | User | Menu. From the Main Menu (press[PREVIOUS] until the Main Menu appears), press Menu [F6], then Setup [F2],and then User [F2].
2. Turn the rotary knob to highlight “Key click” and then highlight either on or off.
3. Press the [ENTER] key to select.

4-8

LOCAL OPERATION

4.3.1.3 Menu | Setup – Units
In addition to the standard units of measure provided by the PPI, four user-defined units
are available. To create a user-defined unit, the user enters a name that is one to ten
characters long and a conversion factor that is a multiple of kiloPascals (kPa).
For example, using the information from table 2-1, the conversion factor for millitorr or
one micron of mercury at 0 °C is calculated as follows.
mTorr = kPa x 1000 mTorr x 1 Torr
1 Torr
1 mmHg 0 °C

x 1 mmHg 0 °C
0.0193377 psi

x 0.1450377 psi
1 kPa

thus the conversion factor simplifies to mTorr = kPa x 7500.6180

MENU | SETUP | UNITS - MENU
1. The pressure units are defined from the Units | Define | Menu. From the Main
Menu (press [PREVIOUS] until the Main Menu appears) press Menu [F6], thenSetup [F2], then Units [F3].
2. Use the rotary knob to highlight the desired user-defined unit, and then select the
Edit Name [F1] function key.
3. The following sequence is used to change the name of the selected unit.

MENU | SETUP | UNITS | EDIT NAME - MENU
4-9

LOCAL OPERATION

a. Use the < [F4] or > [F5] key to highlight the desired character in the matrix.
b. Use the rotary knob to change the character.
c. Repeat steps a and b until the desired name is entered. Press the Clear key tostart over.
d. Press the Done [F6] key when the name change is completed.
4. Use the rotary knob to highlight the desired user-defined unit that has just beenrenamed.
5. Use the numeric keypad to enter the conversion factor and press [ENTER] toaccept.
6. Press [PREVIOUS] three times to return to the Main Menu. The new unit
definition may now be selected using the units key.
4.3.1.4 Menu | Setup – Remote
The Menu | Setup | Remote screen is where the remote communication interface is setup.

Menu | Setup | Remote - Menu
4.3.1.4.1 GPIB Address – Sets the IEEE-488 interface address.
4.3.1.4.2 Protocol – The Protocol defines which protocol should be used by the remoteinterface. The options are Standard Communication for Programmable Instruments(SCPI) which is the standard interface, 6000 to emulate the Ruska Series 6000 pressure
controller, and 510 to emulate the Druck model 510 pressure controller. When using
the SCPI interface, the model 7050 will emulate the Ruska 7010 and 7215 series
controllers.
4.3.1.4.3 Serial Interface Set-Up – The operator can set-up the Baud Rate, Data Bits,
Parity, and Stop Bits for the Serial Interface.
4.3.1.5 Menu | Setup – System
The System Menu identifies the Software release version that is being operated in the
PPI. It also stores and allows the operator to edit the Date and Time.

4-10

LOCAL OPERATIONMENU | SETUP | SYSTEM - MENU
4.3.1.5.1 Date/Time
The PPI’s system clock is continuously updated. If the date or time requires editing, thefollowing applies;
1. The date and time are set from the Setup | System | Menu. From the Main
Menu (press [PREVIOUS] until the Main Menu appears), press Menu [F6], thenSetup [F2], and then System [F5].
2. To set the system date, turn the rotary knob until Date is highlighted. Use thenumeric keypad to enter the current four-digit year, month, and day (yyyymmdd).
All digits must be entered. Press [ENTER] to accept.
3. To set the system time, turn the rotary knob until Time is highlighted. Use thenumeric keypad to enter the current hour, minute, and second (hhmmss). All digits
must be entered. Press [ENTER] to accept.
4.3.1.5.2 Reset
The Reset [F1] command is used to re-boot the PPI.
1. To reset the system, from the Main Menu (press [PREVIOUS] until the Main Menu
appears), press Menu [F6], then Setup [F2], then System [F5], and then Reset[F1].
4.3.2 MENU | CALIBRATEThe Menu | Calibrate command is used to perform the calibrations on all of thesensors utilized by the PPI. The 7050 can be completely calibrated using the front panel
interface. It does not require any external computer or software in order to perform a
successful calibration. It also has the capability of being calibrated remotely througheither the RS232 or IEEE-488 interface. The 7050 will guide the operator through amenu driven calibration procedure identifying the pressures that should be supplied by astandard. Following the calibration procedure, the 7050 calculates and saves its own
coefficients. The calibration coefficients are date stamped so the user can easily identify
the last time the instrument went through a full calibration, when the coefficients were lastedited or when the PPI was re-zeroed.
4-11

LOCAL OPERATIONThe calibration section in the PPI can be password protected to prevent any unauthorized
entry into the calibration section of the system. Please refer to the Maintenance Section(Section 6.0) of the manual for more detailed information regarding the calibration of thePPI.
4.3.2.1 Calibration Password
The calibration password allows the user to protect access to PPI calibration constants
and the calibration procedure. If the calibration password is set to any number otherthan zero, it is required before the user is allowed to calibrate the PPI or manually change
the calibration constants.
IMPORTANT: It is recommended that the access password be recorded and filed in asecure location.
1. The calibration password is set from the Calibration Menu. From the Main
Menu (press [PREVIOUS] until the Main Menu appears), press Menu [F6], thenCalibrate [F3].
2. Press the Access [F4] key. If there is a password in the system other than 0, thenyou must enter the current valid password into the 7050 before it will allow you tomodify the password.
3. Use the numeric keypad to enter the new calibration password. Setting thecalibration password to zero allows free access to PPI calibration and constants.
Press [ENTER].
4. Press Yes [F4] to acknowledge changing the calibration password. Press No [F5]to reject changing the calibration password.
4.3.2.2 Zeroing
Ruska recommends that the PPI be zeroed once a day to maintain optimal performance.
The zero drift specification is defined in Appendix A under General Specifications. Refer
to Section 6.4.5 for the zeroing procedure. On gauge mode instruments, the zeroingprocedure automatically ties both test and reference ports of the Ruska quartz sensor
together and performs the zeroing routine.
On permanent absolute instruments, a vacuum pump and vacuum gauge is required tozero the instrument. The optional vacuum gauge sensor should be installed in a port thatis located internally to the PPI very near to the Ruska quartz sensor. When initiating thezeroing command in the PPI, it will cycle the internal valves allowing the external vacuum
pump to pull a hard vacuum on the Ruska sensor. It is recommended that the sensor bepulled down to a vacuum of less than 200 mTorr (preferably less than 100 mTorr) inorder to obtain a proper zero. The PPI can be zeroed at higher vacuum levels, however,the uncertainty of vacuum sensors tend to increase at higher vacuum levels, therefore, theuncertainty in the PPI would also increase if zeroed at higher vacuum levels. Once thevacuum level is stable, the user enters the vacuum level as indicated by the vacuum
gauge and then the zeroing procedure completes. Please refer to the Maintenance
Section (Section 6.0) of the manual for more detailed information regarding the zeroingprocedure of the PPI.
4-12

LOCAL OPERATION

4.3.3 MENU | TESTThe Menu | Test section of the system is used to perform a number of the diagnostic
and tuning functions that are available with the 7050.

MENU | TEST - MENUMENU | TEST | SWEEP – MENU
4.3.3.1 Menu | Test – Self Test
The PPI can perform electrical and pneumatic self test to assist in trouble shooting
potential problems. Please refer to the Maintenance – Section 6.0 for more details.
NOTE: In order to perform a pneumatic self test, the supply port must be connected toa properly set supply pressure and the test port not open to atmosphere. For
absolute units, a vacuum supply must also be connected to the exhaust port.
4.3.3.2 Menu | Test – Remote Test
The Menu | Test | Remote section of the system is used to perform a number of thediagnostic functions on the remote interface. It can be used to display the transmitted
and received messages that are sent across the interface. This can be a powerful tool toassist in identifying the source of communication problems.
The Menu | Test | Remote menu displays information from the IEEE-488 interface.
Pressing the Serial 1 [F2] or Serial 2 [F3] keys will display information from the serial
ports.

4-13

LOCAL OPERATIONMENU | TEST | REMOTE – GPIB MENUMENU | TEST | REMOTE | SERIAL 1 – MEMU
4.3.3.3 Menu | Test – Shop1
The Menu | Test | Shop1 menu of the system is used to display the current status of thevarious valve positions in the system. This menu is primarily used for diagnostics and will
be discussed further in the Maintenance Section 6.0.
4.3.4 MENU | DISPLAY
The Menu | Display is used to conveniently monitor most of the sensor output
parameters. It is primarily used for troubleshooting.

MENU | DISPLAY – MENU
4.3.4.1 Menu | Display - Blank
This is used as a screen saver in the 7050.

4-14

LOCAL OPERATIONSECTION 5.0
REMOTE OPERATION
5.1 CAPABILITIESThe PPI can be operated remotely by a computer. Two interfaces are supported: IEEE488 and RS-232. Both interfaces support SCPI (Standard Commands for Programmable
Instruments). The IEEE-488 interface additionally supports emulation of a Ruska Single
Channel Interface Panel (Models 6005-701 and 6005-761). The IEEE-488 interface
conforms to the following standards:
ANSI/IEEE Std 488.1-1987 IEEE Standard Digital Interface for Programmable
Instrumentation
ANSI/IEEE Std 488.2-1987 IEEE
Standard
Codes,
Formats,
Protocols,andCommonCommands
SCPI 1991.0
Standard Commands for Programmable Instruments
5.1.1 IEEE-488
The following identification codes define the interface capabilities of the PPI. Identification
codes are described in the IEEE-488 standard.
SH1
AH1
T5
L3
SR1
RL1
PP0
DC1
DT0
C0

Source Handshake, Complete Capability
Acceptor Handshake, Complete Capability
TalkerListener
Service Request, Complete Capability
Remote-Local, Complete Capability
Parallel Poll, No Capability
Device Clear, Complete Capability
Device Trigger, No Capability
Controller, No Capability

The IEEE-488 interface is installed next to the processor board. The interface is identified
by the IEEE-488 standard connector on the back panel of the unit.
NOTE: Do not change any jumpers or switch settings on the IEEE-488 interface board.
The IEEE-488 address is set by the MENU/SETUP/REMOTE screen.
5.1.2 RS-232
The RS-232 interface supports standard serial operation from a computer to a single PPI.
RS-232 supports the IEEE-488.2 and SCPI commands. The PPI allows the following port
setups:Baud Rate:
Data Bits:
Parity:Stop Bits
Handshaking

1200, 2400, 9600, or 19200
7 or 8
Even, Odd, or None
1 or 2
XON/XOFF
5-1

REMOTE OPERATIONThe RS-232 connection is a DB-9P connector found on the back panel of the PPI. It is
located on the processor board. The following pins are used; all other pins are reserved.
Pin #
2
3
5
7

Direction
In
Out
——
Out

SignalRXD Receive DataTXD Transmit Data
GND Ground
RTS Request to Send

5.2 REMOTE/LOCAL OPERATION
In Local mode, the PPI is operated manually through the front panel. Section 4.0 covers
local operation. The PPI always powers up in the Local mode. In Remote mode, the PPI
is operated by a computer connected to an interface. Most functions that can be
performed in Local mode can also be performed remotely.
Remote mode does not automatically disable local operation. The remote interface may
be active while local operations are being done. In cases where full remote control isrequired, the following methods may be used.
1. Issue a Local Lockout (LLO) interface message via the IEEE-488 interface. The PPI
will disable the local keyboard until the Go To Local (GTL) interface message is
received or the REN (Remote Enable) line is unasserted. This method cannot be
used on the serial interface.
2. Issue the SCPI command “SYSTEM:KLOCK ON” to lock the local keyboard. The
PPI will disable the local keyboard until the command “SYSTEM:KLOCK OFF” isreceived.
3. Issue the SCPI command “DISPLAY:ENABLE OFF” or “DISPLAY:TEXT <string>.”
These commands will disable the local display in addition to locking the keyboard.
The command “DISPLAY:ENABLE ON” will restore the local display and keyboard
operation.
Local operation may also be restored by turning the PPI off and back on.
5.3 CONFIGURATIONThe remote interface must be configured before it is connected. The remote interface isconfigured using the local interface. The parameters needed vary with the interface
used.
IEEE-488
RS-232

Address, Protocol
Baud Rate, Data Bits, Parity, Stop Bits

To configure the remote interface:
1. The remote interface is configured from the Setup | Remote | Menu. From theMain Menu (press [PREVIOUS] until the Main Menu appears), press Menu [F6],then Setup [F2], and finally Remote [F4].
2. Use the rotary knob to highlight the desired parameter.
3. Use the numeric keypad to enter the address; use the rotary knob to change theother parameters. The [ENTER] key must be pressed after entering the address.
5-2

REMOTE OPERATION

4. Repeat steps 2 and 3 to set all parameters needed.
5.4

DEVICE MESSAGES

5.4.1 SCPI COMMAND FORMATSCPI mnemonics have two forms: long and short. The short form is all in capital letters.
The long form is the entire mnemonic. Commands may use either the short form or theentire long form. No other forms are accepted. SCPI ignores case: uppercase andlowercase are equivalent.
A SCPI command is made by following the command tree as presented in the commandsummary. Each level adds a mnemonic to the command separated by colons (:).
Mnemonics enclosed in square brackets are optional and may be omitted.
Some mnemonics are followed by an optional numeric suffix.
defaults to 1.

If omitted, the suffix

Multiple commands may be placed in a single message separated by semicolons (;).
Each command starts at the same level of tree where the last command stopped, unlessthe command starts with a colon. The first command in a message and any commands
starting with a colon start at the root of the command tree. IEEE 488.2 commands may
occur between SCPI commands without affecting the tree level.
Command parameters are separated from the command name by one or more spaces.
Multiple parameters are separated by commas (,). SCPI accepts numeric parameterswith optional sign, decimal point, and exponent. OFF is equivalent to zero and ON isequivalent to one. Floating point numbers are rounded to the nearest integer forcommands accepting integer values only.
A message is terminated by a line feed (hexadecimal 0A). Carriage returns, tabs, andother control characters are ignored.
5.4.2 SCPI RESPONSE FORMAT
Most values can be queried by appending a question mark (?) to a command and not
specifying any parameters. Commands ending with a question mark (?) in the commandsummary cannot be set only queried. Multiple values from a single command areseparated by commas. Responses from different commands in the same message are
separated by semicolons (;). The response message is terminated by a line feed(hexadecimal 0A).
Integer responses are returned as one or more digits. Boolean values (ON and OFF
values) are always returned as numbers, with zero for OFF and one for ON. Floating
point values are returned in the format “+d.ddddddddE+dd.”

5-3

REMOTE OPERATION

5.4.3 ANSI/IEEE 488.2-1987 COMMAND SUMMARY
*CLS
*ESE?
*ESE
<number>
*ESR?
*IDN?
*OPC?
*OPC
*RST
*SRE?
*SRE
<number>
*STB?
*TST?
*WAI

Clear Status
Event Status Enable Query
Event Status Enable
Event Status Register
Identification
Operation Complete Query (Returns 1)
Operation Complete
Reset
Service Request Enable Query
Service Request Enable
Status Byte Query
Self-Test Query
Wait (No operation)

5.4.4 SCPI COMMAND SUMMARY
The current value associated with a SCPI command may be read by appending aquestion mark to the command. For example CALC:LIM:UPP? will return the current
upper pressure limit.
MEASure[:PRESsure]?
:TEMPerature2?
:TEMPerature3?
:PRESsure2?
:PRESsure3?
:SLEW?
CALCulate:LIMit:LOWer <number>:SLEW <number>:UPPer <number>:TARE:VALUE <number>:STATe ON/OFF
CALibration[:PRESsure]

Returns Current Pressure Reading
Returns Oven Temperature
Returns Oven 2 Temperature (7250xi only)
Return Case Pressure
Return Barometric Reference Pressure
Returns Pressure Slew Rate (units/sec)
Get/Set Low Pressure Limit
Get/Set Slew Rate Limit
Get/Set High Pressure Limit
Get/Set Tare Value
Set Tare state using current pressure:VALue<n> <number>:DATA:POINts?
:VALue<n>?
:VALue<n> <number>:CALibration:POINts?
:VALue?
:DATE?
:TIME?

Perform calibration point
Number of calibration constants
returns cal. constant label, value
Set calibration constant
Number of calibration points
Nominal calibration point
Last calibration date
Last calibration time:ZERO
:VALUE<number>

Performs Zero Calibration
Sets Vacuum Value
5-4

REMOTE OPERATION

:INITiate:INITiate?

Enter Zero Calibration Mode
Status for Cal, Pressure, Temp., ReferenceCal:
0=Not Zeroing,
1=Local Zero,
2=Remote Zero
Pressure, Temperature, Reference:-1=Out of Range
0=Stable>0=Time until stable
Start Zero Calibration
Last zero date
Last zero time

:RUN
:DATE?
:TIME?
:PRESsure2 Case reference sensor:VALue<n> <number>
Perform calibration point:DATA:POINts?
Number of calibration constants:VALue<n>?
returns cal. constant label, value:VALue<n> <number>
Set calibration constant:CALibration:POINts?
Number of calibration points:VALue?
Nominal calibration point:ZERO <number>
Zero sensor to value:PRESsure3 Reference sensor
Same as PRESsure2 above:PRESsure4 PDCR sensor
Same as PRESsure2 above:VACuum
Same as PRESsure2 above:TEMPerature
Gas Temperature
Same as PRESsure2 above:TEMPerature2
High Sensor Temperature
Same as PRESsure2 above:TEMPerature3
Low Sensor Temperature
Same as PRESsure2 above:MODE?
return 1 if calibration edit enabled:MODE <access code>
Request calibration edit
DISP
:ENABle ON|OFF|1|0
Turns Front Panel Display On/Off
TEXT <string>
Displays Message on Front Panel:BGRaph<number> Sets Bar Graph Maximum
SENSE[:PRESSure][:RESolution] <number>
Set Pressure Display Resolution:AUTO<boolean>|ONCE
Return to Default Resolution:MODE?
Returns ABSOLUTE or GAUGE:MODE ABSolute|GAUGe
Turns On or Off Simulated Absolute:RANGE[:UPPer]?
Returns PPI Full Scale Value in Units:LOWer?
Returns Lowest Calibrated Value:REFerence[:HEIGht] <number>
Set Gas Head Height
5-5

REMOTE OPERATION

:MEDium N2|AIR
STATus:OPERation[:EVENT]?
:CONDition?
:ENABle<number>:QUEStionable[:EVENT]?
:CONDition?
:ENABle <number>:PRESetSet Gas Medium
Read/Clear Operation Event Register
Read Operation Condition Register
Set Operation Enable Mask
Read/Clear Questionable Event Register
Read Questionable Condition Register
Set Questionable Enable Mask
Reset Condition Flags

SYSTem:DATE <year>,<month>,<day>:ERRor?

Set System Date
Returns <error#,”descr;info”>
Or 0,”No Error”
Lock Keyboard
Set System Time
Returns 1991.0
Set Interface Protocol to 6000 or SCPI, or
Druck DPI-500
Reset System:KLOCk ON|OFF|1|0:TIME <hour>,<minute>,<second>:VERSion?
:LANGuage “6000”|”SCPI”|"500":PRESetTEST:ELECtronic?
:STOP
UNIT
:DEFine<n> <name>,<number>:LENGth MM|IN[:PRESsure] <unit name>

Perform Electronic Self-Test
Abort Pneumatic Self-Test
Define a Unit
Set Length Units for Head HeightSet Pressure Units. Valid unit names are
KPA, BAR, PSI, KG/CM2, MMHG0C,
CMHG0C, INHG0C, INHG60F
CMH2O4C, INH2O20C, INH2O25C, %FS,
FT, M, KNOT, KM/HR, MPA, PA

5.4.5 EXAMPLE SCPI COMMANDS
To request the current pressure reading, all of the following commands are equivalent::MEASURE:PRESSURE?
:measure:pressure?
:MeAsUrE:pReSsUrE?
:meas:pres?
:measure?
:meas?
MEAS?

To zero the unit via the remote interface use the following sequence:
CAL:ZERO:INIT
CAL:ZERO:INIT?

Enter Zero Mode
Read Status (Mode, Pressure, Temperature, Reference)and Wait Until Stable.

CAL:ZERO:RUN

Start Zero Adjust Sequence
5-6

REMOTE OPERATIONSTAT:OPER:COND?

Wait Until Complete (Bit 0 = 0)

5.4.6 SCPI STATUS REGISTERS
Three type of status registers are available: Condition, Event, and Enable.
Condition registers always show the current status of the instrument. Bits may turn on
and back off between reads. The status read is the status of instrument at the moment of
the read. Condition registers include:
*STB?
*ESR?
STAT:OPER:COND?
STAT:QUES:COND?

Status Byte Register
Standard Event Status Register
Operation Status Condition Register
Questionable status Condition Register

Event registers do not show the current state but flag the bits in the condition registers
that have changed since the last time the event register was read. When an event
register is read it is reset to zero.
STAT:OPER:EVENT?
STAT:QUES:EVENT?

Operation Status Event Register
Questionable Status Event Register

Enable registers are set by the user to create summary bits. If the user sets a bit in theenable register, when the instrument sets the corresponding bit in the event register asummary bit in the Status Byte Register is set.
*ESE
STAT:OPER:ENAB
STAT:QUES:ENAB
The Service Request Enable Register (*SRE) is used to generate service requests on theIEEE-488 bus. If a user sets a bit in this register, when the instruments sets thecorresponding bit in the Status Byte Register (*STB) a service request is generated.
*SRE
Status Byte Register (STB), Service Request Enable Register (SRE)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0

Operation status summary. Set when an event enabled in OPER:ENABLE occurs.
Service request. Set when an event enabled in SRE occurs. (This bit is not used in SRE.)
EBS - Event status bit. Set when an event enabled in ESE occurs.
MAV - Message available. Set when a response is ready to be sent.
Questionable status summary. Set when an event enabled in QUES:ENABLE occurs.
Error/event queue not empty.
Reserved. 0.
Reserved. 0.

Standard Event Status Register (ESR), Standard Event Status Enable Register (ESE)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2

Power-on. Set at power-up.
Reserved 0.
Command error. Error in command syntax.
Execution error. Error in command execution.
Device dependent error. Device error independent of commands.
Query error. Output queue empty when request received.
5-7

REMOTE OPERATION

Bit 1
Bit 0

Reserved. 0.
Operation complete. Set for *OPC command.

Operation Status (OPER:EVENT, OPER:CONDITION, OPER:ENABLE)
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 7
Bit 8
Bit 9
Bit 10
Bit 11
Bit 12
Bit 13
Bit 14
Bit 15

Calibrating. Currently performing a calibration.
Settling. Control setpoint has not been reached. Pressure tolerance set by
SOUR:PRES:TOL
Reserved. 0.
Reserved. 0.
Measuring. The instrument is actively measuring.
Reserved. 0.
Reserved. 0.
Self-test in progress.
Reserved.
Reserved. 0.
Reserved. 0.
Reserved. 0.
Reserved. 0.
Program running.
Reserved. 0.

Questionable Status (QUES:EVENT, QUES:CONDITION, QUES:ENABLE)
Bit 0 Reserved.
Bit 1 Reserved. 0.
Bit 2 Time is questionable. Set when the clock has not been set.
Bit 3. Temperature is questionable. Sets when oven temperature is not within range.
Bit 4 Reserved. 0.
Bit 5 Reserved. 0.
Bit 6 Reserved. 0.
Bit 7 Calibration is questionable. Set when the unit has not been calibrated.
Bit 8 Pressure is questionable. Set when the pressure is overranged.
Bit 9 Reserved. 0.
Bit 10 Reserved. 0.
Bit 11 Reserved. 0.
Bit 12 Reserved. 0.
Bit 13 Reserved. 0.
Bit 14 Command warning. Set whenever a command ignores a parameter.
Bit 15 Reserved. 0.

5.5 6005 INTERFACE PANEL EMULATIONThe PPI may be configured to emulate the IEEE-488 command set of the Ruska Single
Channel Interface Panel (Models 6005-701 and 6005-761). See the Interface Panel
User’s Manual for a description of the protocol. The PPI emulation has the following
differences:
1. The PPI is always in Remote mode (Byte 1, Bit 1) .
2. All TI strip outputs must be written as OFF.
3. No special functions are implemented.
4. Any message written to the PPI that starts with a colon as the first character isinterpreted as a SCPI command.
5-8

REMOTE OPERATIONTo change from SCPI to Interface Panel Emulation via the remote interface, send thefollowing message::SYSTem:LANGuage “6000”.
To change from Interface Panel Emulation to SCPI via the remote interface send thefollowing message::SYSTem:LANGuage “SCPI”.
5.6 SERIAL OPERATIONThe RS-232 port accepts the same SCPI commands as the IEEE-488 port. The
commands can be terminated by a carriage return (hexadecimal 0D) or a line feed(hexadecimal 0A). The responses are always terminated by a carriage return followed bya line feed.
The serial port also supports XON/XOFF. When the XOFF (hexadecimal 13) command isreceived, the PPI will stop transmitting. Transmission is restarted when the XON(hexadecimal 11) command is received.
When only one unit is attached, the Control-C (hexadecimal 03) command will clear thetransmit and receive buffers and disable addressing. When addressing is disabled, theunit will respond to commands without being addressed.
5.7

DRUCK DPI-510 EMULATION COMMAND SUMMARY

5.7.1

SUPPORTED COMMANDS
B <value>
C0
C1
D0, D2
D1
Fxx
I0
I1
I2
I3
I4
I5
I6
I7
J0,J1,J2
M
N0,N1,N2,N3,N4
O1
P<value>
R0
R1,R2
S0,S1,S2,S3
T0
T1
U1 to U23

Set Tare amount
Go to MEASURE mode.
Go to CONTROL mode.
Transmit Pressure Reading
Transmit Setpoint(Ignored)
Disable SRQ
SRQ on In Limit
SRQ on Error
SRQ on In Limit and Error
SRQ on End of Conversion
SRQ on Error and End of Conversion
SRQ on In Limit and End of Conversion
SRQ on In Limit, Error and End of Conversion
Set Pre-programmed rate.
Unlock keyboard
Set talk mode notation
Zero
Set pressure Setpoint
Unlock keyboard
Lock keyboard
Set pre-programmed units
Turn off Tare mode
Turn on tare mode to value set to B (B must be set first)
Set S4 units (if S4 is selected this will change current units
5-9

REMOTE OPERATION

V<value>W<value>/0 to /11
*0 to *11
@0
@1

5.7.2

immediately)
Set slew rate (sets low overshoot mode)
Set In Limit wait time
Set setpoint as fraction of P value
Set pre-programmed setpoint
Disable error reporting
Enable error reportingRESPONSE FORMATS
N0<Pressure or Setpoint><REM|LOC>RnSnDn[@nn]N1<Pressure or Setpoint>[@nn]
N2<REM|LOC>RnSnDnCnInFn
N3<In Limit Status>[@nn]N4@nEnJnVnnnnUaaaa

NOTE: Secondary addressing is not supported.
5.7.3 RESET CONDITIONS
N0 D0 F0 I0 @1 R0 S0 W002
5.7.4 KEYBOARD ENTRY
MENU/SETUP/REMOTE/510EMUL
Termination:
CR/LF/EOI, CR/EIO, LF/EOI, or EOIZero Delay:
Delay for zero stabilization.
F1,F2,F3 Rates
Specify rates used by J0, J1, J2
MENU/SETUP/REMOTE/510EMUL/F1UNIT
MENU/SETUP/REMOTE/510EMUL/F2UNIT
MENU/SETUP/REMOTE/510EMUL/F3UNIT
Select units for S0, S1, S2
MENU/SETUP/REMOTE/510EMUL/RATIOSSpecify ratios used by /0 to /11
MENU/SETUP/REMOTE/510EMUL/PRESETS
Specify presets used by *0 to *11
5.7.5 NOTESFormatUpper and lower case are equivalent. Spaces and equal signs are ignored before
numeric values. Spaces, commas, semi-colons, and colons are ignored before and after
commands.

5-10

REMOTE OPERATION

Zeroing
The Ruska sensor takes longer to zero. This time can be set from the front panel. The
default is 5 seconds but this may need to be increased especially for absolute units.
When the zero command is received the zeroing valve is opened, the system waits thezero delay time and then the sensor is zeroed.
Rate
If the rate is positive it will be used at the maximum rate with the overshoot set to low. If
the rate is zero then the maximum rate will be used with the overshoot set to low. If therate is negative the maximum rate will be used with the overshoot set to normal.
Units

5.8

Unit Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23

Unit Name
Pa
kPa
Mpa
mbar
bar
kg/cm2
kg/m2
mmHg
cmHg
mHg
mmH2O
cmH2O
mH2O
torr
atm
psi
lb/ft2inHg"H2O04'H2O04SPEC'L"H2O20'H2O20Ruska display units
kPa
kPa
kPa
bar
bar
kg/cm2kg/cm2mmHg 0oC
cmHg 0oC
cmHg 0oC
cmH2O 4oC
cmH2O 4oC
cmH2O 4oC
mmHg 0oC
bar
psi
psi
inHg 0oC
inH2O 4oC
inH2O 4oC
User Defined 1
inH2O 20oC
inH2O 20oC

SAMPLE PROGRAMS

5.8.1 SAMPLE PROGRAM 2 - 7050 GPIB (IEEE-488)- ZERO SEQUENCE/*------------------------------------------------------------*//*
Sample Program 2 - 7050 GPIB (IEEE-488)
*/
/*
*/
/*
Zero Sequence*//*------------------------------------------------------------*/#include <stdio.h>#include <stdlib.h>#include <string.h>#include <conio.h>
5-11

REMOTE OPERATION

#include "decl.h"/*------------------------------------------------------------*/
int
device;charbuffer[256];
double pressure;int
status;/* GPIB Device descriptor *//* buffer for input/output strings *//* Pressure read from unit *//* Status register from unit */int
check_errors (void);
int
zero (void);
void
write_7000 (char *s);void
request_7000 (char *s);/*------------------------------------------------------------*/
void main (void){char *p;/*---------------------------*//* Initialize GPIB Interface *//*---------------------------*/
device = ibdev (0,/* First GPIB Board */4,/* GPIB Address of 7250 */NO_SAD,/* No secondary addressing */T1s,/* 1 Second Timeout */0,

REOS+LF);/* No automatic EOI for transmit *//* Terminate read on Line Feed */if (ibsta & ERR)
{ cprintf ("GPIB Driver not installed.\n");return;}}/*-----------*//* Zero 7010 *//*-----------*/
if (!zero ( )){ ibonl (device, 0);
return;}/*----------------------*//* Reset GPIB Interface *//*----------------------*/
ibonl (device, 0);

5-12

REMOTE OPERATION

/*------------------------------------------------------------*//* Zero : perform zero adjust of 7250*//*------------------------------------------------------------*/
int zero (void){
int cstat, pstat, tstat, rstat;clrscr ( );cprintf ("Zeroing");
gotoxy (1, 5); cprintf ("Pressure Reading");
gotoxy (1, 6); cprintf ("Sensor Temperature");gotoxy (1, 7); cprintf ("Reference Pressure");/*-------------------*//* Enter Zero Mode*//*
CAL:ZERO:INIT *//*-------------------*/
write_7000 ("CAL:ZERO:INIT\n");/*-------------------------------------------------*//* Wait for calibration values to be within limits *//*CAL:ZERO:INIT?
*//*-------------------------------------------------*/
do{ if (kbhit ( )){ getch ( );break;}
request_7000 ("CAL:ZERO:INIT?\n");sscanf (buffer, "%d,%d,%d,%d", &cstat, &pstat, &tstat, &rstat);if (check_errors ( ))return 0;
gotoxy (20, 5);
if (pstat == 0)
cprintf ("Stableelse if (pstat < 0) cprintf ("Out of Range

");
");

else if (pstat > 0) cprintf ("Unstable (%2d seconds)", pstat);gotoxy (20, 6);
if (tstat == 0)
cprintf ("Stable");else if (tstat < 0) cprintf ("Out of Range");else if (tstat > 0) cprintf ("Unstable (%2d minutes)", tstat);gotoxy (20, 7);
if (rstat == 0)

cprintf ("Stable");5-13

REMOTE OPERATION

else if (rstat < 0) cprintf ("Out of Range");else if (rstat > 0) cprintf ("Unstable (%2d seconds)", rstat);}while (pstat != 0 || tstat != 0 || rstat != 0);/*-------------------*//* Start Zero Adjust *//*CAL:ZERO:RUN *//*-------------------*/
write_7000 ("CAL:ZERO:RUN\n");/*---------------------------*//* Wait for zero to complete *//*STAT:OPER:COND?
*//*---------------------------*/
do{ request_7000 ("STAT:OPER:COND?\n");sscanf (buffer, "%d", &status);
if (check_errors ( ))return 0;
gotoxy (1, 9);cprintf ("Zeroing");}
while ((status & 1) != 0);
gotoxy (1, 9);cprintf ("Zero Complete");return 1;}/*------------------------------------------------------------*//* check_errors : display all GPIB and 7250 error messages*//*
return TRUE if any errors were found*//*------------------------------------------------------------*/
int check_errors (void){
unsigned char status7;
int retval;/*---------------------------------*//* Check for GPIB Interface Errors *//*---------------------------------*/
if (ibsta & ERR)
5-14

REMOTE OPERATION

{ cprintf ("GPIB Status=%4X Error=%d\r\n", ibsta, iberr);
return 1;}/*-----------------------*//* Check for 7250 Errors *//*-----------------------*/
retval = 0;
while (!kbhit ( )){ ibrsp (device, &status7);
if ((status7 & 4) == 0)
break;
retval = 1;
request_7000 ("SYST:ERR?\n");cprintf (buffer);}
return retval;/* Serial poll *//* Check error bit *//* Get error message */}/*------------------------------------------------------------*//* write_7000 : write a command to the 7250*//*------------------------------------------------------------*/
void write_7000 (char *s){
ibwrt (device, s, strlen (s));}/*------------------------------------------------------------*//* request_7000 : write a query command and read the response *//*------------------------------------------------------------*/
void request_7000 (char *s){
ibwrt (device, s, strlen (s));
ibrd (device, buffer, sizeof (buffer));}/*------------------------------------------------------------*/

5-15

REMOTE OPERATIONTHIS PAGE INTENTIONALLY LEFT BLANK

5-16

REMOTE OPERATIONSECTION 6.0
MAINTENANCE
6.1 INTRODUCTION
Very little maintenance is required for the PPI. This section of the manual discusses
suggested maintenance procedures.
6.2 OBSERVING THE SOFTWARE VERSION NUMBER
Follow the steps below to observe the PPI’s software version number.
1. If necessary, press [PREVIOUS] several times to return the display to the Main
Menu.
2. Select MENU | SETUP | SYSTEM. The software version number will appear on
the screen.
3. Press [PREVIOUS] to return to the previous screen.
6.3 PREVENTIVE MAINTENANCE
Although the PPI is designed to be nearly maintenance free, occasional preventive
maintenance is required to keep the PPI’s performance optimal.
6.3.1

INITIATING THE PPI’S SELF TESTTo test the PPI’s hardware, software, and pneumatics, follow the steps below.
1. If necessary, press [PREVIOUS] several times to return the display to the Main
Menu.
2. Select MENU | TEST | SELF

MENU | TEST | SELF - MENU
3. Press ELECTRICAL [F1]. The electronics self test will run and display the results.
4. Press [PREVIOUS] to return to the previous screen.
The electronics test runs eight sets of tests on various parts of the electronic modules.
Table 6-1 describes these tests and the possible actions needed if a test fails. The
pneumatics test runs nine tests on the pneumatics module.
6-1

MAINTENANCETABLE 6-1
ELECTRONICS SELF TEST
Test
Processor

Description
Tests the processor chip

Clock

Tests the real time clock

Timer

Tests the 10 ms interval timer

EEPROM

Tests the nonvolatile memory

Oven

Tests operation of the sensor
ovenAction on failure
Replace processor
board.
Replace processor
board.
Replace processor
board.
Replace processor
board.
Replace sensor assy.
Allow oven to warm up.

RIC Part #7215-586-3
7215-586-3
7215-586-3
7215-586-3
Contact Ruska

CAUTION: The PPI should only be opened by qualified electrical/mechanical service
technicians. Lethal voltages are present and exposed in the power supply anddisplay.
1. Turn off the PPI and disconnect the power cord from the PPI.
2. Locate and unscrew the four screws that secure the cover to the back panel.
3. Place your hands near the middle of the cover and slide the cover towards the
PPI’s back panel.
4. Lift up on the cover. With the cover removed, use typical electronic cleaning tools
to remove any accumulated dust from inside the instrument.
5. Replace the cover before resuming operation.
6.3.2 MOISTURE FILTER
The Bourdon tube sensor is hydroscopic. An external desiccant filter prevents introductionof moisture and is strongly recommended for high humidity areas. The filter should be
replaced annually. The moisture filter is used with the reference port only (absolute only
instruments do not need a moisture filter).
6.3.3 PARTICLE FILTERS
Refer to Appendix A for air supply quality requirements. During normal operation, the PPItransfers gas both into and out of the device under test (DUT). When necessary, the user
is expected to use and maintain an in-line disposable particle filter to protect the PPI’s
pneumatics from any contamination that may exist in the DUT.
6.3.4 VACUUM PUMPS
Periodic checks of the user’s vacuum pumps for oil levels. It is very highly recommended
that a power-down vacuum venting valve is installed onto the vacuum pumps to ensure
minimal chances of oil contamination from the vacuum sources. These are normallyopen solenoid valves that are powered through the vacuum pump power switch. Whenthe vacuum pump is turned on, the solenoid valve is energized and closes allowing thepump to operate normally. When the pump is turned off, power is removed from the
6-2

MAINTENANCE

solenoid and the vacuum is vented to atmosphere. Periodic changing of vacuum pump
oil as recommended by the vacuum pump manufacturer should also be done.
6.3.5 PROCESSOR BATTERY
The processor board uses a lithium battery to maintain time and date information. Thisbattery has a varying life. If the instrument is left on 24 hours a day, it may last 5 to 10
years. If the instrument is stored, it may only last one year. Annual replacement isrecommended. To replace the battery:
1. Turn off power and remove the instrument cover.
2. Remove the processor card by removing the screw and the bracket that locks thedisplay cable in place and gently rock the card upward.
3. Holding the processor card, remove the battery (the round silver object), by
carefully pulling on the battery.
4. Plug in a new battery (RIC # 4-725).
5. Reinstall the processor card, the bracket that locks the display cable in place andthe screw. Replace the instrument cover.
6. The time and date may have to be re-entered. See Section 4.3.1.5.1.
6.4 CALIBRATION
To keep the PPI operating within its specified precision, the calibration proceduredescribed below should be performed once every year. If a higher level of overall
performance is desired, the user can calibrate more frequently.
NOTE: The calibration procedure automatically generates coefficients that are stored
in memory on the PPI’s. If these constants are “lost” for any reason, thecalibration procedure must be performed, regardless of the last calibration date.
If the calibration coefficients have been recorded, they may be restored to the PPIat any time by “editing the coefficients” (Section 6.4.3).
6.4.1 CALIBRATION INSTRUCTIONS
To calibrate the PPI, the user connects a calibration standard such as the Ruska
Instrument Model 2465 (or 2470 for high pressure ranges) Gas Piston Gauge to the PPI’s
test port, then follows the multi-step calibration procedure on the PPI’s display. The
standard PPI requires a positive pressure calibration. A vacuum (negative gauge) option
is available and requires special calibration per Section 6.4.2. No disassembly isrequired and there are no potentiometers to tune.
NOTE: The uncertainty of the final calibration must include the uncertainty of thepressure standard being used.
6.4.1.1

Preparation

1. Verify that the PPI’s Reference Port is open to atmosphere for gauge calibrations
and that the calibration standard is connected to the Test Port.

6-3

MAINTENANCE

2. Verify that the PPI has been at stable environmental temperature and that the oventemperature (MENU | DISPLAY) has been stable for at least three hours.
3. Verify that the PPI is in Measure mode (Section 4.0).
4. If desired, change the PPI’s units of measure (Section 4.0) to match those of thecalibration standard.
5. Set the gas head to 0. Select MENU | SETUP | USER.
6. To access the calibration screen, select MENU | CALIBRATION.

7. When you first enter the Calibration menu, the top left hand side of the display will
indicate which sensor is being the viewed. The sensors coefficients are then shown
below the sensor label. The first sensor that is shown is the primary measuring
sensor. This is indicated by the word Primary displayed in the top of the display.
To cycle through the various sensors that exist in the system, you would press the
Sensor [F6] function key. Assure that you are in the screen that is labeled asPrimary.
8. To begin the calibration process, press the Calibrate [F2] button. If thecalibration access code is enabled, enter it at the prompt. The first calibration
screen will appear.
NOTE: To exit the calibration procedure before the calibration coefficients have beenchanged, press [CANCEL] any time during the procedure. Canceling restores all
previous calibration values.
Step 1
1.1 To begin step 1 of the calibration process, select Zeroset [F1]. The zeroprocedure will start when the reading is in-range and stable or when OK[F6] is pressed. Press OK [F6] only if the zeroing conditions are stable. The
zero calibration will not be accurate if OK [F6] is pressed when conditions
are unstable.
1.2 Wait until the zero procedure finishes. This may take several minutes. Whenthe PPI completes step 1, the calibration screen will appear.
6-4

MAINTENANCE

PR

RE

HIGH

On High Pressure Models, pressure must be removed from the test
port. If zeroing an Absolute unit then the Test Port must be isolated.

ESSU

Step 2
2.1

To begin step 2, use the calibration standard to apply the various pressuresthat will be requested by the 7050. The number of pressure points required
to calibrate the PPI will vary based on whether the PPI is a 7050, 7050i or
7050LP and if it has a vacuum (negative gauge) option. The screen will
display a table noting the following information;
Step – The pressure step in the calibration sequence
Apply – The pressure that the standard is to generate to the PPI.
Tolerance – The tolerance about the apply value that can be generated by
the standard and still accepted by the PPI.
Actual – The actual pressure value that was generated by the standard when
the point was accepted.
Adj. %FS – Depicts the amount that the PPI corrected its output to align tothe standard. This is used as a trouble-shooting tool. If one point has asignificantly higher adjustment required than other points in the calibration,
this may indicate that there was an error in that specific calibration point.
The operator can re-check this pressure point prior to completing andaccepting the full calibration.
2.2
The Step 1, actual value will be highlight. This is your first pressure point in
the calibration procedure.

NOTE: If the PPI has the Vacuum (Negative Gauge Option) or the Barometricreference, the first two points in the procedure will show the negative pressuresthat should be generated to calibrate the sensor in the negative gauge direction.
You are not required to perform both the negative and the positive gauge
calibrations every time the unit is calibrated. If you want to calibrate only the
positive pressures, using the rotary knob move the highlighted curser down to thefirst positive pressure step and generate all of the positive pressures in theprocedure. When you are complete with the positive points, hit the Done key, theunit will maintain the older coefficients for the negative gauge portion of thesensor and calculate new coefficients for the positive gauge ranges. Conversely,
you can calibrate just the negative gauge section if desired. However, you mustcomplete all of the positive or negative gauge steps in the procedure to complete
a valid calibration.
2.3 Using your calibration standard, generate the pressure shown in the Applycolumn. When the measured pressure stabilizes, use the PPI’s numeric
keypad to enter the actual pressure applied by the calibration standard and
6-5

MAINTENANCE

then press ENTER. Do not enter the measured pressure reported by the PPI. If
necessary, use the [CLEAR] key to correct a mistake in the edit field. If theactual pressure applied is within the indicated tolerance, the unit will accept
that point and the highlighted curser will automatically scroll down to the next
calibration step.
NOTE: If the actual pressure is outside of the tolerance for the requested mid-point
pressure, Error —222 Data out of range will occur. Acknowledge this error by
selecting OK [F6], then re-enter the actual pressure, repeating step 2.1 ifnecessary.
Step 3
3.1

3.2

Generate the next pressure calibration point requested by the PPI. Apply
this pressure using calibration standard and follow the instructions in Step
2.3, entering the actual pressure applied.
Repeat this procedure until all of the calibration steps are complete. Review
the Adj. %FS field to see if one point has a significantly higher adjustment
required than other points in the calibration. This may indicate that there
was an error in that specific calibration point. The operator can re-checkthis pressure point prior to completing and accepting the full calibration.
To re-enter a point, use the rotary knob and move the highlighted curser tothe actual pressure values in the step in question. Generate the requested
apply pressure using the standard and enter then new actual value whenstabilized.

6.4.1.2 Storing the Coefficients
Step 4
4.1 Calibration is complete. To exit the calibration procedure without storing thecalibration coefficients in memory, press [CANCEL]. To store the calibration
coefficients in memory, select the Done [F6] key and the PPI will calculate allof its new coefficients.
NOTE: In additional to saving the calibration coefficients to the PPI's memory, the useris advised to separately record the calibration coefficients and store this "backup"
in a safe place.
Step 5
5.1 Press [PREVIOUS] to return to the Main Menu.
5.2 Once the calibration procedure is complete, the user should verify several
pressure readings against the pressure standard. If there are variances
beyond the stated precision, then an error was probably made in generating
one of the calibration pressures, and the calibration procedure should be
repeated.

6-6

MAINTENANCE

6.4.2VACUUM (NEGATIVE GAUGE) CALIBRATIONS
Vacuum mode is an available option. The following configuration should be used whencalibrating in the Vacuum mode.

FIGURE 6-4
VACUUM CALIBRATION
To calibrate in Vacuum mode with the configuration shown in Figure 6-4, the following
actions should be taken. The system pressure and vacuum inlet valve should remainclosed. The bottom side of the piston must be open (vented) to atmosphere andconnected to the reference port of the DUT. The test port of the DUT must be connectedto the bell jar with a cutoff valve to isolate it from the DUT. Additionally, there must be acutoff valve located between the Vacuum pump and the bell jar.
Close the Cut-off valve to isolate the DUT test port from the bell jar. Open the Vacuum
Pump Valve to pull a hard vacuum on the bell jar to seal the bell jar and to float themasses. Once the masses have risen in response to evacuation of the bell jar, close thereference vacuum pump cutoff valve. Use the metering valve on the bell jar to adjust(vent) the bell jar vacuum towards atmosphere until the masses begin to float. Close themetering valve as soon as the masses begin to float. Open the bell jar cutoff valve to thetest port of the DUT, close the exhaust (Vent) valve, and use the pressure adjuster
handwheel to adjust float position of the deadweight gauge to float the piston at midfloat position.

6-7

MAINTENANCE

6.4.3 RPT CALIBRATION - SIMULATED ABSOLUTE
A span correction can be applied to the RPT (barometric) sensor. This correction is doneusing the PPI software and can be performed without removing the RPT from the PPI
chassis.
1. Place the PPI in Measure mode. Remove all pressure sources from the system.
2. Connect a pressure standard to the Reference Port of the PPI.
3. If desired, change the PPI’s units of measure (see Section 4) to match those of thecalibration standard.
4. To access the Calibration screen, from the Main Menu, select MENU |CALIBRATE.
5. Select the atmospheric sensor by pressing the Sensor [F6] key until the words
Atmospheric Sensor is displayed above the calibration coefficients.
6. To begin the calibration process, press CALIBRATE. If the calibration access codeis enabled, enter it at the prompt. The first Calibration screen will appear.
7. You will use the calibration standard to apply the various pressures that will be
requested by the 7050. The screen will display a table noting the following
information;a. Step –the pressure step in the calibration sequence.
b. Apply – The pressure that the standard is to generate to the PPI.
c. Actual – The actual pressure value that was generated by the standard when
the point was accepted.
8. The Actual value will be highlighted. This is your first pressure point in thecalibration procedure. This calibration requires the generation of two pressures
within the range of 700 to 1100 mbar absolute. The selected pressures should bespaced as far apart as possible within the allowable range.
9. Generate the first pressure. Enter the actual value of the applied pressure
generated by the standard and press [ENTER].
10. Generate the second pressure. Enter the actual value of the applied pressure
generated by the standard and press [ENTER].
11. The RPT sensor is now linearly compensated. Once the calibration procedure iscomplete, the user should verify several pressure readings against the pressure
standard. If there are variances beyond the stated precision, then an error wasprobably made in generating one of the calibration pressures, and the calibration
procedure should be repeated.
12. Remove the pressure source from the Reference Port.
6.4.4 EDITING THE CALIBRATION COEFFICIENTS
If the PPI’s memory is erased but the calibration coefficients are known, the user can
restore the coefficients to the PPI by following the directions below.

6-8

MAINTENANCE

CAUTION: Never randomly adjust the calibration coefficients.
Only qualified
personnel with valid backup data should be allowed to edit the coefficients. If the
backup coefficients are questionable, perform the calibration procedure in its
entirety.
1. Verify that the PPI is in Measure mode (Section 4.0).
2. Enter the Calibration screen by selecting MENU | CALIBRATE.
3. When you first enter the Calibration menu, the top line of the display will indicate
which sensor is being the viewed. The sensors coefficients are then shown below
the sensor label. The first sensor that is shown is the primary measuring sensor.
This is indicated by the word Primary displayed in the top of the display. To cycle
through the various sensors that exist in the system, you would press the Sensor[F6] function key. The two common sensors that would be calibrated would be
the Ruska sensor which would be labeled as Primary and if the unit has theoptional Barometric Reference sensor, this would be labeled as AtmosphericSensor.
4. To edit the calibration coefficients, press the EDIT button. If the calibration accesscode is enabled, enter it at the prompt. The first calibration screen will appear.
NOTE: To exit the calibration procedure before the calibration coefficients have beenchanged, press [CANCEL] any time during the procedure. Canceling restores all
previous calibration values.
5. Use the rotary knob to highlight the coefficient to be edited. The terms arecoefficients of a linear regression analysis.
6. Use the numeric keypad and the [ENTER] key to enter a new value. To correct a
mistake in the edit field, use the [CLEAR] key.
7. Repeat steps 4 and 5 until all coefficients are correct.
NOTE: In addition to saving the calibration coefficients to the PPI’s memory, separately
record the calibration coefficients and store this “backup” in a safe place.
8. To exit the editing procedure without storing the calibration coefficients in memory,press [CANCEL]. To store the calibration coefficients in memory, select DONE
[F6].
9. Press [PREVIOUS] to return to the Main Menu.
Once the calibration coefficients are input, the user should record several pressure
readings. If there are any variances beyond the stated precision at these points, then thecalibration procedure should be performed.
6.4.5 ZEROING
The zeroing procedure is performed to correct for system zero shift and does not requirea full calibration. The most important requirement for performing a valid zeroing

6-9

MAINTENANCE

procedure is to guarantee that there is not a pressure differential between the sensor’s
test port and case reference.
If during the zeroing procedure, the message “Mechanical Zeroing Needed” appears,
the sensor photocell may need to be zeroed. See Section 6.5 for more information.
The zeroing screen presents several pieces of information.
The screen will display the current status of the pressure sensor Stability andTemperature.
If any of the above are unstable, then the system will delay until stability is achieved.
Pressing OK [F6] will bypass this wait period.
NOTE: Bypassing this wait period can have a negative effect on the zeroingprocedure.
6.4.5.1 Gauge and Vacuum (Negative Gauge) Instruments
1. Verify that the Reference Port is open to atmosphere.
2. Enter the Calibration screen by selecting MENU | CALIBRATION.
3. Select Zero [F1]. Do NOT press the Calibrate button.

4. Do not disturb the instrument while zeroing is in process.
5. Wait for the zeroing procedure to finish.
6. Press [PREVIOUS] to return to the Main Menu.

6-10

MAINTENANCE

6.4.5.2 Absolute Instruments
A vacuum pump must be connected to the reference port.
A vacuum gauge should be installed for measuring the case reference pressure. Thisgauge should be installed as close to the sensor as possible. There is an 1/8-inch NPT
fitting available for this installation inside the PPI near the sensor.
1. Select the desired pressure units using the UNITS key. You can change both theunit of measure that the PPI is displaying Pressure and the unit of measure for thevacuum sensor. It is not required to have the PPI displaying pressure in the same
unit of measure as the vacuum sensor. To change the unit of measure for the
Vacuum sensor, press the UNIT key and then the Vacuum [F2] key.
2. Enter the Calibration screen by selecting MENU | CALIBRATE.
3. Select Zero [F1]. Do NOT press the Calibrate button. When initiating the zeroingcommand in the PPI, it will cycle the internal valves allowing the external vacuum
pump to pull a hard vacuum on the Ruska sensor. It is recommend that the sensor
be pulled down to a vacuum of less than 200 mTorr (preferably less than 100
mTorr) in order to obtain a proper zero. The PPI can be zeroed at higher vacuum
levels, however, the uncertainty of vacuum sensors tend to increase at higher
vacuum levels, therefore, the uncertainty in the PPI would also increase if zeroed at
higher vacuum levels.
4. Wait for the vacuum level on the test port to stabilize.
5. Enter the vacuum level as read by the external vacuum gauge and press OK [F6].
6. Do not disturb the instrument while zeroing is in process.
7. Wait for the zeroing procedure to finish.
8. Press [PREVIOUS] to return to the Main Menu.

6-11

MAINTENANCE

6.4.5.3 RPT - Simulated Absolute Instruments
Simulated absolute PPI’s contain two sensors that require periodic zeroing. The primarysensor is zeroed according to the instructions in Section 6.4.5.1 or 6.4.5.2. The
barometric sensor is zeroed according to the following instructions.
1. Verify that the Reference Port is open to atmosphere.
2. Enter the Calibration screen by selecting MENU | CALIBRATE.
3. Select the Atmospheric Sensor by pressing the Sensor [F6] key until the words
Atmospheric Sensor is displayed above the calibration coefficients.
4. To begin the zeroing process, press ZERO. If the calibration access code isenabled, enter it at the prompt. The zeroing screen will appear.
NOTE: The next step requires the use of a properly calibrated standard. This zeroingprocess does contribute directly to the overall accuracy of the system, since thepressure applied to the sensor is a non-zero differential pressure.
5. Enter the current barometric pressure. Press [ENTER].
6.5 SENSOR PHOTOCELL ZEROING
If the error message “Mechanical Zeroing Needed” is displayed, the sensor photocell
must be zeroed. The following steps describe this process.
CAUTION: The PPI should only be opened by qualified electrical/mechanical service
technicians. Lethal voltages are present and exposed in the power supply anddisplay.
NOTE: The sensor MUST have zero differential between the Test port and Reference
port. For Gauge PPIs, apply atmospheric pressure to the Reference port. For
Absolute PPIs, apply a vacuum to the Reference port (<200 µHg.)
1. Remove the PPI’s top cover.
2. Locate and remove the plastic zeroing plug located in the side of the sensor ovenassembly.
3. Enter the Zeroing screen by selecting MENU | CALIBRATE.
4. Select the Primary sensor by pressing the Sensor [F6] key until the words Primaryis displayed above the calibration coefficients.
5. Select Zero [F1]. Do NOT press the Calibrate button.
6. Select the Mechanical Zero [F1] key.

6-12

MAINTENANCE

7. Referring to Figure 6-5, slightly loosen the Allen screw on the back of the sensor
bracket, making sure to maintain a snug fit on the screw. Using the T-shaped
Photocell Centering Tool (RIC # 7250-111), adjust the photocells by placing thetool in the hole in the back of the sensor and turning the tool slightly. The screen
will show a number of horizontal lines. The top yellow bar represents the current
zero setting. The bottom portion of the bar has a green bar in the center and two
red bars on either end. If the top yellow bar is over the red bar, then mechanicalzeroing is required. If the yellow bar is over the green bar, then no adjustment isrequired.

8. Adjusting the photocell will cause the yellow bar to reduce in width. You want toadjust the photocell until the yellow line is as thin as possible over the green bar.

9. Tighten the Allen screw.
10. Often, when the Allen screw is tightened, the zero will move. Review the width of
the yellow line, again loosen the Allen screw, and now offset the yellow bar the

6-13

MAINTENANCE

11.
12.
13.
14.
15.

same width that you observed it moving from tightening the Allen screw, and now
offset it in the opposite direction by this same width.
Again, tighten the Allen screw. Now the width of the yellow line should be
minimized.
Tap on the bracket with a screwdriver handle to relieve mechanical stress.
Continue to tap on the bracket until the counts stop changing.
If the zero moved significantly as a result from tapping the bracket, repeat thisprocedure as necessary.
Reinstall plastic zeroing plug.
After the unit has become thermally stabilized, perform a normal instrument
zeroing procedure. Refer to Section 6.4.5.

FIGURE 6-5
PHOTOCELL LOCATION
6.6 FAN OPERATION
The fan in the 7050 can be turned on or off. It is recommended to keep the fan ON
since this will extend the life of the power supply.
When operating the system in either a very cold or hot environment, if the oven is unable
to maintain the temperature of the internal oven, it will generate error Oven Control
Failure Error messages. The operator can review the temperature and duty cycle of theoven by pressing the MENU | DISPLAY keys. The unit must have been warmed up for aminimum of 2 hours prior to determining the condition of the oven temperature control.
The temperature of the sensor should be controlled to 50o C. The Duty cycle indicatesthe percentage of time that the oven control is turned on in order to maintain the oven at
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MAINTENANCE

the proper set-point of 50o C. A unit that is operating properly, after it has fully warmed
up, should indicate a sensor temperature of 50o C and a duty cycle between 10 to 90%.
If operating the instrument in a very cold environment and the oven duty cycle is at ahigh percentage (>90%) you will need to turn the fan off. If you are operating in a warm
environment or when multiple systems are housed in consoles without adequate
ventilation, the system may become too hot and generate the oven control failure error
message. If operating the instrument in a warm environment and the oven duty cycle is
at a low percentage (>10%) you will need to turn the fan on.
When the operator changes the status of the fan, it will default to that condition until it ischanged by the operator.

MENU | TEST| SHOP 1 – MENU
To turn the fan on or off, press Menu [F6] from the Main Menu, then Test [F5], thenShop1 [F5].
Use the rotary knob to highlight either fan Off or On. Press [ENTER] to select.
6.7

SYSTEM SOFTWARE UPDATE PROCEDURE

NOTE: Calibration and other stored constants are not affected by program updates.
The update procedure requires a PC connected to the RS-232 port on the 7XXX. (9-pin to
9-pin, null modem cable minimum pinout 2-3, 3-2, 5-5).
1. When appropriate, Ruska can e-mail the latest version of the software for
upgrading instruments. The e-mail will have a zip file attached contains two files
UPDATE7.EXE and <version>.IMG. Unzip these files into a directory on the PC.
2. Set the 7XXX to 9600 baud, 8 databits, no parity, 1 stopbit.
3. Run the program Update7.
4. Follow the prompts to select the communications port and the image file.
5. When the upgrade is finished, Update7 running on the PC and the 7XXX shouldboth display Complete.

6-15

MAINTENANCE

6.8 REPLACEMENT PARTS
The following is a list of the common replacement parts used in the Model 7050 PPI.
Part Number
88-1055
11-763
11-7647000-70
7000-717250-111
62-29323-9067250-100-005
7215-PCA-KEY

Description
Zeroing ValveTFT Display
Display Inverter Electronic Board
Sensor LED Lamp Assembly
Sensor Photocell
Photocell Adjustment Tool
Power Supply
Fan
Rotary Encoder
Front Panel Keyboard Electronic Card

6-16

MAINTENANCESECTION 7.0
PREPARATION FOR STORAGE & SHIPMENT
NOTE: The procedures given in sections 7.1 through 7.3 must be strictly adhered to inorder to prevent damage to the instrument. Failure to follow these procedures will
likely result in damage to the PPI during shipment. This damage is not covered by
the carrier’s insurance.
7.1

DISCONNECTING THE PPI

1. Relieve all pneumatic pressure from the PPI.
2. Turn the PPI power switch to the off position.
3. Disconnect the power cable from the PPI power receptacle.
4. Disconnect all pneumatic lines from the PPI’s back panel.
5. Plug all ports.
7.2 PACKING INSTRUCTIONS
To prevent shipping and handling damage to the instrument, adhere to and strictly follow
the instructions below.
The governing discipline in ensuring a damage-free shipment is to ensure that thepossibility of handling shocks to the PPI is minimized and/or prevented during transit.
Ruska accomplishes this task by cradling the PPI within two foam cradles that are
encapsulated within a double-walled, corrugated box. The PPI is restrained andsupported, but still has resilience. The materials used in the packaging operation are
foams that have a minimum impact rating of not less than N-95.
Styrofoam, poured “foam in place” mixtures, and other rigid foams are notrecommended.
If polyfoam or rubber foam other than that used in the original packaging is to be used,
cut it into strips so that it will not present a large rigid surface to the PPI.
Ruska has found that corrugated cardboard boxes provide the best packaging exterior.
The box must have an impact rating of 275 lb and be of double-walled construction.
This type of box will sustain most types of damages incurred during the shipping andhandling process, but ensures that the contents remain intact and damage-free. The
foam cradle ensures that a minimum of 3 inches of foam separates the inner surface ofthe box and any portion of the PPI. Wood or metal boxes do not absorb shock when
dropped and therefore are not recommended.
If the original packaging and shipping materials have been retained, use them forpacking the PPI. If the PPI is being packed for long-term storage (more than 30 days),place a desiccant bag inside the box.

7-1

STORAGE & SHIPMENTThe PPI must be prepared for shipment in the following manner:
1. Ruska Instrument has an RMA procedure in place. Please contact the Customer
Service Center to obtain an RMA number prior to returning any equipment to
Ruska. Have the following information available when contacting Ruska:
a. the part number,b. the serial number,c. the purchase order number,d. the billing and ship to address, ande. the buyer’s name and telephone number.
This information plus the RMA number must be attached to the unit when it isshipped to Ruska Instrument. There will be a minimal charge for inspection
and/or evaluation of returned goods.
2. Enclose the PPI in plastic or any good water barrier material. Antistatic material isrecommended.
3. If the original shipping carton is not usable or available, use a double-walled
corrugated carton with a 275-lb rating. The recommended carton size is 25 1/2 x
19 1/2 x 12 3/8 inches.
4. Insert one foam cradle from the original shipment onto the floor of the box. (Theoriginal foam cradles are of the same type of construction and are completelyinterchangeable.) If the foam cradles are not available, cover the bottom andsides with no less than 3 inches of N–95 foam strips. Arrange the strips in theconfiguration illustrated in figure 7-1.
5. Before sealing the carton, include the following:a. Statement of the problem or service needed. Be specific. Include the nameand telephone number of a knowledgeable technician for consultation.
b. The part number, serial number, return address, and purchase order number.
6. Seal the carton using gummed tape.
7. Address the carton to:
RUSKA INSTRUMENT CORPORATION
10311 WESTPARK DRIVE
HOUSTON, TX 77042
USA
8. Label the carton with the following labels: THIS SIDE UP, HANDLE WITH CARE,
DO NOT DROP, and FRAGILE. (If the original Ruska shipping carton is utilized forthis shipment, the above markings are preprinted on the carton.)

7-2

STORAGE & SHIPMENTFIGURE 7-1
PACKING THE PPI
7.3 SHIPPING INSTRUCTIONS
Ruska recommends using air freight for transportation. Surface transportation subjects
the shipment to more frequent handling and much more intense shock. In most cases, if
surface transportation is the mode of transport employed, handling damage is likely.
Again, it is essential that the procedures mentioned in sections 7.1 through 7.3 be strictly
adhered to in order to prevent any shipping and handling damage to the instrument.

7-3

STORAGE & SHIPMENTNOTES

7-4

STORAGE & SHIPMENTAPPENDIX ASUMMARY OF SPECIFICATIONS
A.1 UNCERTAINTY ANALYSIS
To perform an Uncertainty Analysis on a measurement device, you must be able toidentify all of the parameters that influence the measurement. You must be able toquantify the magnitude of the potential error source and combine these into an overall
uncertainty statement.
To determine the expanded uncertainty on any manufacturers pressure Transfer Standard(TS), you must identify the following four primary influences;
1.) Performance specifications of the TS
2.) Long term Stability of TS
3.) Uncertainty of the standard used to calibrate the TS4.) Environmental or installation influences that could cause errors in the TS
Performance Specifications are the short-term measurement properties of the device.
These traditionally include linearity, hysteresis, and repeatability properties of the transfer
standard. There often is considerable confusion with the performance specification
because different manufacturers use different terms to describe the performance
characteristics of their instruments. The two most common terms used are “Accuracy”
and “Precision”. In both cases, as a minimum the manufacturers define these terms tobe the combined effects of linearity, hysteresis and repeatability. Since the manufacturer
defined the terms they used, this should not be a problem. However, it is common thatthe users definition of these terms differ from the manufacturers and therefore cause
considerable confusion. For instance, the user may believe that the term “Accuracy”
includes all sources of uncertainty. This would include items 1 through 4 listed above
which would be an all encompassing specification. The manufacturer may define“Accuracy” as the performance specification which consist only of item 1 above. The
result would be that the instrument would not be capable of meeting the users
application because it would not meet the users definition of “Accuracy”.
Long Term Stability defines how the instrument drifts with time. This specification canbe utilized to define the calibration interval for the standard. Some manufacturers will
provide more than one stability specification for their instrument based on different
calibration time intervals. It is important to understand that you should not arbitrarily
vary the manufacturers stability specification based on time without knowing thecharacteristics of their device.
Some manufacturers identify that their stability
specification is proportional with time. Therefore, if the calibration interval were reducedin half, the magnitude of the stability specification would also be halved. This can be a
powerful tool when you are trying to improve the measurement performance of astandard. By reducing the calibration interval, the expanded uncertainty would also
reduce. On the other hand, some manufacturers do not claim that their stability
specification is proportional with time. This would be the case for instance if the
instrument naturally drifted in a sinusoidal fashion. This would suggest that the sensor
A-1

APPENDIX A

could drift to its maximum stability limit at any time and therefore, reducing thecalibration interval would not improve the expanded uncertainty of the device.
Uncertainty of the Standard used to calibrate the transfer standard. This is the
expanded uncertainty of the calibration standard that was used by the manufacturer tocalibrate the digital transfer standard. This should be the expanded uncertainty of thecalibration standard and include all sources of uncertainty that would influence thecalibration standard including the uncertainty from the National Standards Laboratorythat the standard is traceable.
It should also be noted that when the instrument is re-calibrated, the uncertainty of thedevice is influenced by the uncertainty of the calibration standard that will be used toperform the re-calibration. Therefore, the uncertainty analysis should be evaluatedfollowing each re-calibration. If the instrument is re-calibrated using a different
calibration service provider than the manufacturer, the uncertainty of the standard thatthe calibration service provider used to perform the calibration would need to be
substituted for the manufacturers calibration uncertainty that was used in the original
uncertainty analysis.
Environmental or Installation Influences that could cause errors in the transfer
standard. This includes influences such as ambient temperature, line pressure, headpressure, time response, and controller effects. (It may include other influences that arevery specific to one manufacturers instrument.) It is recommended that the intended
application is reviewed to assure that the environmental does not impact the instruments
performance, or that the impact from the environment is accounted for in the uncertainty
analysis. For instance, if an instrument has a 0.001%FS per degree Celsius temperatureeffect from a calibrated temperature of 20 degrees Celsius, and the instrument is to be
used in an environment where the temperature will vary from 15 to 25 degree Celsius,then a +/- 0.005% of full scale uncertainty should be included in the uncertainty analysis
for ambient temperature effects.
Combining the Uncertainty Components into an Expanded Uncertainty Statement
Once all of the uncertainty components are identified, they can be combined into an
overall Expanded Uncertainty Statement for the instrument. The vast majority of themeasurement community has adopted a statistical approach to uncertainty analysis suchas the International Organization for Standards (ISO) Guild to the Expression ofUncertainty in Measurement. This statistical approach combines all of the uncertainty
components in quadrature (RSS).
In this approach, it is important to define the level of confidence that all of the uncertainty
components are defined. For instance, all of the uncertainty specifications that Ruska
Instrument Corporation publishes are at the 2 sigma level which would be at a 95%
confidence level. Some manufacturers may state their uncertainty at different confidence
level and therefore, you would need to be able to convert from one to the other in order
to compare the two devices. For instance, if a manufacturer states that they have an
uncertainty of 0.005% FS and that the uncertainty is expressed at the 1 sigma level, then

A-2

APPENDIX A

it would be doubled to express it at the 2 sigma level (i.e. it would be an 0.01% FS device
at a 2 sigma or 95% confidence level.)
The following two tables are uncertainty analysis examples for a 7250i based on a threemonth and a yearly calibration.
Uncertainty Analysis – 3 Month Calibration Interval
Ruska Model 7050i from 25 to 100% of Range
A. Performance – (Linearity, Hysteresis, Repeatability
and Temperature)
B. Stability – (3 months)

Uncertainty(2 sigma)
0.005% of Reading
0.0019% of Reading per 90 days

C. Calibration Standard – (Ruska Model 2465 DWG)

0.0010% of Reading

D. Environmental –Temperature (Included in A. above)

0.000% of Reading

Head Pressure

0.001% of Reading

2 sigma Expanded Uncertainty (RSS)

Uncertainty Analysis – One Year Calibration Interval
Ruska Model 7050i from 25 to 100% of Range
A. Performance – (Linearity, Hysteresis, Repeatability
and Temperature)
B. Stability – (1 year)

0.0055% of Reading per 90 days

Uncertainty(2 sigma)
0.005% of Reading
0.0075% of Reading / year

C. Calibration Standard – (Ruska Model 2465 DWG)

0.0010% of Reading

D. Environmental –Temperature (Included in A. above)

0.000% of Reading

Head Pressure

0.001% of Reading

2 sigma Expanded Uncertainty (RSS)A-3

0.009% of Reading per year

APPENDIX AThe following two tables are uncertainty analysis examples for a single range 7250
based on a three month and a yearly calibration.
Uncertainty Analysis – 3 Month Calibration Interval
Ruska Model 7050
A. Performance – (Linearity, Hysteresis, Repeatability
and Temperature)
B. Stability – (3 months)

Uncertainty(2 sigma)
0.003% of Full Scale
0.0019% of Reading per 90 days

C. Calibration Standard – (Ruska Model 2465 DWG)

0.0010% of Reading

D. Environmental –Temperature (Included in A. above)

0.000% of Reading

Head Pressure

0.001% of Reading

2 sigma Expanded Uncertainty (RSS)

Uncertainty Analysis – One Year Calibration Interval
Ruska Model 7050
A. Performance – (Linearity, Hysteresis, Repeatability
and Temperature)
B. Stability – (1 year)

0.003% of Full Scale RSS with
0.0024% of Reading per 3
months

Uncertainty(2 sigma)
0.003% of Full Scale
0.0075% of Reading / year

C. Calibration Standard – (Ruska Model 2465 DWG)

0.0010% of Reading

D. Environmental –Temperature (Included in A. above)

0.000% of Reading

Head Pressure

0.001% of Reading

2 sigma Expanded Uncertainty (RSS)A-4

0.003% of Full Scale RSS with
0.0076% of Reading per year

APPENDIX A

A.2

SPECIFICATIONSGENERAL SPECIFICATIONS
Pressure Range:

Minimum; 0 to 5 (0 to 700 mbar)
Maximum; 0 to 3000 psi (0 to 200 bar)

Display:

6.4 inch, TFT Active Matrix Color

Display Resolution:User-selectable up to 1:1,000,000

Electrical Power:

90–260 VAC, 47 - 63 Hz (50-400 Hz for i models), 150 W

Operating Temperature:

18–36°C

Storage Temperature:–20–70°C

Humidity:

5–95% relative humidity, non-condensing

Dimensions:7" H x 16.5" W x 19" D (17.8 cm x 41.9 cm x 48.3 cm)

Weight:7250i: 16 lb (7.25 kg)

Standard Pressure Units:inHg at 0°C and 60°F, kPa, bar, psi, inH2O at 4oC, 20, and 25°C, kg/cm2, mmHg at 0°C, cmHg at 0°C, and cmH2O at 4°C

Pneumatic Ports:

1

Relief Valves:

Test Port: 120% of Maximum Scaled Quartz Sensor Range
Reference: 10 Psig (where applicable)/4-inch NPT female

A-5

APPENDIX APERFORMANCETABLE A-1
PERFORMANCE SPECIFICATIONS

Precision1
Stability
Zero Drift4

7050

7050i

7050LP

0.003% FS

From 25% to 100% FS: 0.005% RDG
Below 25%FS: 0.005% of 25%FS

0.005% of eachRange

0.0019% RDG/3 months or 0.0075% RDG/year
0.004%FS / 24hrs

0.002%FS / 24hrs

0.004%FS / 24hrs

Neg. Gauge
Precision1

0.003% of max
positive FS

Greater of 0.005% of 25%FS or
0.0005 psi (3.5 Pa)

0.005% of max FS(Optional 0.005%
of each range)

Barometric
Reference3

0.002 psi / year
(14 Pa / year)

0.002 psi / year
(14 Pa / year)

N/A

VacuumReference3

0.0002 psi / year
(1.33 Pa / year)

0.0002 psi / year
(1.33 Pa / year)

N/A

Options:1

Precision is defined as the combined effect of linearity, repeatability, and hysteresis throughout theoperating temperature range. Some manufacturers use the word “Accuracy” in place of “Precision”,
however the meaning is identical.
2
Zero drift improves with sensor age.
3
Additional Uncertainty when operating a gauge mode 7050 or 7050i in the absolute mode. This
uncertainty component would be combined RSS with the gauge mode uncertainty of the instrument.

A-6

APPENDIX AAPPENDIX B
SUMMARY OF ERROR MESSAGES
Negative error numbers are from the Standard Commands for Programmable Instruments(Version 1991.0).
Value

Description and Corrective Action

0
-103
-104
-109
-110
-113
-114
-221

No Error.
Invalid Separator. Check punctuation in the SCPI command.
Data Type. The type of parameter data is incorrect.
Missing Parameter. No valid parameter was found for the SCPI command.
Command Header. The command name is not valid.
Command Unknown. The command specified does not exist.
Header Suffix. The numeric suffix for the command name is out of range.
Settings Conflict. The command could not be executed due to the current state of the
PPI. Some commands cannot be executed while a program, self-test, or calibration isin progress.
Out of Range. The value is not within the valid range. For pressures check high andlow limits.
Cannot create program. Program memory is full.
Illegal Program Name. The name specified is not valid or does not exist.
Program Currently Running. The command cannot be executed while a program isrunning.
Program Syntax Error. The syntax of the program definition is not correct.

-222
-281
-282
-284
-285

-330

Program Runtime Error. An error occurred while running the program. Usually the
setpoint is out of range.
Calibration Data Lost. The calibration data has been lost and the unit must berecalibrated.
Configuration Data Lost. The configuration data has been lost. Check all parameters
to be sure they are correct.
Self-Test Failed. Check the display for the test that failed.

-350

Queue Overflow. The error queue was full and messages were lost.

-400

Query Error. A read request was received when there was nothing to read.

500

Controller Malfunction. Internal control failure.

501

High Limit Exceeded. The pressure was greater than the high limit.

502

Low Limit Exceeded. The pressure was less that the low limit.

503

Slew limit Exceeded. The pressure changed faster than the slew limit allowed.

521

Pressure Overrange. The pressure reading is outside the range of the PPI.

531

Oven Temp Overrange. Either the transistor that drives the heater for the quartz
Bourdon tube sensor (section 2) or the oven temperature sensor itself is malfunctioning.
To observe the oven temperature, select OK then select MENU/DISP. Check thetransistor and sensor for malfunction, requesting service (section 7) if necessary.

-286
-313
-315

B-1

APPENDIX B

533

Case Pressure Overrange. Select OK, then reduce the pressure at the casereference port to 30 psia or lower.

540

Mechanical Zeroing Needed. The zero point of the quartz Bourdon sensor isbeyond the range of the compensation circuit. The zero is adjusted by thesoftware but should be manually adjusted for complete accuracy.

542

Oven Control Failure. The temperature controller is unable to keep the sensor at
the proper temperature.

545

Sensor Communication Error. Unable to Communicate with 7215xi Sensor

546

Sensor Calibration Lost. The 7215xi sensor has lost its calibration and must berecalibrated.

600

Factory Data Lost. Internal factory constants have been lost. Contact Ruska for
more information.

601

Calibration Mode. The Calibrate button must be pressed before SCPI calibrationcommands can be executed.

800

Solenoid Over-Temperature. The control solenoids have over-heated. Wait until
they have cooled before entering Control mode.

801

Error reading Barometric RPT Pressure Sensor

802

Control Sensor out of range

803

Controller Communication Error

804

Autotune Failed

B-2

APPENDIX B