Title Page

UM-23652-AA

User’s Manual forStandard TEMPpoint, VOLTpoint,
and MEASURpoint LXI
Instruments
DT8871, DT8871U, DT8872, DT8873, DT8874

Copyright Page

Trademark and Copyright Information
Measurement Computing Corporation, InstaCal, Universal Library, and the Measurement
Computing logo are either trademarks or registered trademarks of Measurement Computing
Corporation. Refer to the Copyrights & Trademarks section on mccdaq.com/legal for more
information about Measurement Computing trademarks.
Other product and company names mentioned herein are trademarks or trade names of theirrespective companies.
© 2018 Measurement Computing Corporation. All rights reserved. No part of this publication
may be reproduced, stored in a retrieval system, or transmitted, in any form by any means,electronic, mechanical, by photocopying, recording, or otherwise without the prior written
permission of Measurement Computing Corporation.

NoticeMeasurement Computing Corporation does not authorize any Measurement Computing
Corporation product for use in life support systems and/or devices without prior written consent
from Measurement Computing Corporation. Life support devices/systems are devices or systems
that, a) are intended for surgical implantation into the body, or b) support or sustain life and whose
failure to perform can be reasonably expected to result in injury. Measurement Computing
Corporation products are not designed with the components required, and are not subject to thetesting required to ensure a level of reliability suitable for the treatment and diagnosis of people.

FCC
Page

Radio and Television InterferenceThis equipment has been tested and found to comply with CISPR EN55011 Class A andEN61326-1 requirements and also with the limits for a Class A digital device, pursuant to Part
15 of the FCC Rules. These limits are designed to provide reasonable protection against
harmful interference when the equipment is operated in a commercial environment. Thisequipment generates, uses, and can radiate radio frequency energy and, if not installed andused in accordance with the instruction manual, may cause harmful interference to radio
communications. Operation of this equipment in a residential area is likely to cause harmfulinterference, in which case the user will be required to correct the interference at his own
expense.
Changes or modifications to this equipment not expressly approved by Data Translation could
void your authority to operate the equipment under Part 15 of the FCC Rules.

Note: This product was verified to meet FCC requirements under test conditions that
included use of shielded cables and connectors between system components. It is importantthat you use shielded cables and connectors to reduce the possibility of causing interference
to radio, television, and other electronic devices.

Canadian Department of Communications Statement
This digital apparatus does not exceed the Class A limits for radio noise emissions fromdigital apparatus set out in the Radio Interference Regulations of the Canadian Department ofCommunications.
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les limites
applicables aux appareils numériques de la class A prescrites dans le Règlement sur lebrouillage radioélectrique édicté par le Ministère des Communications du Canada.

Table of Contents

Table of Contents
About this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Intended Audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
How this Manual is Organized . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Conventions Used in this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Related Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Where To Get Help. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Chapter 1: Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Hardware Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
TEMPpoint Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
VOLTpoint Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
MEASURpoint Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Supported Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Getting Started Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

Part 1: Getting Started . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Chapter 2: Preparing to Use theInstrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Checking the System Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Installing the Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Prerequisite Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Installation Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Viewing the Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Chapter 3: Setting Up and Installing
the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Connecting the Instrument to the LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Connecting to a Site LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Connecting to a Private LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Connecting Using a Hub or Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Connecting Directly to a Computer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Applying Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Getting an IP Address and Host Name. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Determining Ethernet Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Resetting the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Chapter 4: Wiring Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
General Wiring Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

5

Contents

Warm-Up Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Connecting Thermocouple Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Connecting RTD Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
4-Wire RTD Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
3-Wire RTD Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
2-Wire RTD Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Connecting Voltage Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Connecting Voltage Inputs to Thermocouple Channels . . . . . . . . . . . . . . . . . . . . . . . . . 55
Connecting Voltage Inputs to RTD Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Connecting Voltage Inputs to Voltage Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Connecting Current Loop Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Connecting Current Loop Inputs to Thermocouple Channels. . . . . . . . . . . . . . . . . . . . 60
Connecting Current Loop Inputs to RTD Channels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Connecting Current Loop Inputs to Voltage Channels . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Connecting Digital I/O Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Connecting Digital Input Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Connecting Digital Output Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Chapter 5: Configuring the Instrument
Using the Web Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Before Using the Web Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Java Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Internet Explorer Browser Settings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
JavaScript . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Security Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Internet Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Local Intranet Zone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Trusted Sites Zone. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Pop-up Blockers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Associating CSV Files with Microsoft Excel or Notepad . . . . . . . . . . . . . . . . . . . . . . . . 74
Locating Your Instrument on the LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Running the Eureka Discovery Utility. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Configuring Windows Firewall Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Launching the Web Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Configuring the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
LAN Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Channel Configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Scan Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Filter Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Alarm Limits Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Digital Input and Trigger Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Digital Output Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86

6

Contents
Measuring Data and Controlling the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Starting and Stopping a Scan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Controlling the Digital Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Reading the Digital Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Downloading Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Part 2: Using Your
Instrument. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Chapter 6: Principles of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
DT8871U Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
DT8871 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
DT8872 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
DT8873 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
DT8874 Block Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Analog Input Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Analog Input Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Thermocouple Input Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Cold Junction Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Open Thermocouple Detection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
RTD Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Input Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Out of Range Data for Thermocouple Channels . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Out of Range Data for RTD Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Out of Range Data for Voltage Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Resolution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Sample Clock Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Trigger Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Conversion Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Simultaneous Single-Value Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Continuous Scan Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Specifying Analog Input Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
How Continuous Scan Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Filtering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Data Format for Thermocouple Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Data Format for RTD Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Data Format for Voltage Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Digital I/O Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

7

Contents

Digital Input Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
Digital Output Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Channel-to-Channel Functional Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Resolution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Operation Modes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Chapter 7: Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
General Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
If Your Instrument Needs Factory Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Appendix A: Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Basic Instrument Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Thermocouple Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
System Temperature Error for the DT8871U and DT8874 . . . . . . . . . . . . . . . . . . . . . . 124
System Temperature Error for the DT8871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
RTD Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Temperature Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Voltage Measurement Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Isolation and Protection Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Memory Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Digital I/O Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Power, Physical, and Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Regulatory Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Connector Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
Thermocouple Connectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
RTD Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Voltage Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Ethernet (RJ45) Connector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
External Power Supply Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Appendix B: Connector Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Appendix C: Configuring Network Settings onYour PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Configuring the PC to Use Auto-IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Specifying a Static IP Address for your Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Reconfiguring the PC to Use a Static IP Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

8About this Manual
TEMPpoint is a family of temperature measurement instruments that includes the DT9871,
DT9871U, DT8871, DT8871U, DT9872, and DT8872. This manual describes the DT8871,
DT8871U, and DT8872 Ethernet LXI (LAN eXtensions for Instrumentation) models.
VOLTpoint is a family of voltage measurement instruments that includes the DT9873 andDT8873. This manual describes the DT8873 LXI model.
MEASURpoint™ a family of mixed temperature and voltage measurement instruments that
includes the DT9874 and DT8874. This manual describes the DT8874 LXI model.

Note: For information on the DT9871, DT9871U, DT9872, DT9873, and DT9874 USB models
of TEMPpoint, VOLTpoint, and MEASURpoint, refer to the User’s Manual for Standard
TEMPpoint, VOLTpoint, and MEASURpoint USB Instruments.

The first part of this manual describes how to install and set up your instrument, and verify
that the instrument is working properly.
The second part of this manual describes the features and capabilities of your instrument
using the IVI-COM instrument driver software. Troubleshooting information is also provided.

Note: If you are programming the instrument using the IVI-COM driver, refer to the
DtxMeasurement IVI-COM driver online help for more information.
If you are using Standard Commands for Programmable Instruments (SCPI) to program yourinstrument, refer to the SCPI Programmer’s Manual for MEASURpoint for more information.

Intended Audience
This document is intended for engineers, scientists, technicians, or others responsible forusing and/or programming a TEMPpoint, VOLTpoint, or MEASURpoint instrument. It is
assumed that you have some familiarity with thermocouples, RTDs, and/or voltages and thatyou understand your application.

9About this Manual

How this Manual is OrganizedThis manual is organized as follows:• Chapter 1, “Overview,” summarizes the major features of the TEMPpoint, VOLTpoint,
and MEASURpoint instruments, as well as the supported software and accessories.
• Chapter 2, “Preparing to Use the Instrument,” describes how to unpack the instrument,
check the system requirements, install the software, and view the documentation online.
• Chapter 3, “Setting Up and Installing the Instrument,” describes how to apply power tothe instrument and connect the instrument to the network.
• Chapter 4, “Wiring Signals,” describes how to wire signals to the instrument.
• Chapter 5, “Configuring the Instrument Using the Web Interface,” describes how to
configure the instrument using the instrument’s web interface.
• Chapter 6, “Principles of Operation,” describes the analog input and digital I/O featuresof the TEMPpoint, VOLTpoint, and MEASURpoint instruments in detail.
• Chapter 7, “Troubleshooting,” provides information that you can use to resolve problems
with your instrument, should they occur.
• Appendix A, “Specifications,” lists the specifications of the TEMPpoint, VOLTpoint, and
MEASURpoint instruments.
• Appendix B, “Connector Pin Assignments,” describes the pin assignments of the digital
I/O connector on the TEMPpoint, VOLTpoint, and MEASURpoint instruments.
• Appendix C, “Configuring Network Settings on Your PC,” describes how to configure the
network settings of your PC to use Auto-IP or a static IP address.
• An index completes this manual.

Conventions Used in this Manual
The following conventions are used in this manual:• Notes provide useful information or information that requires special emphasis, cautions
provide information to help you avoid losing data or damaging your equipment, andwarnings provide information to help you avoid catastrophic damage to yourself or yourequipment.
• Items that you select or type are shown in bold.
•

CAUTION – This icon denotes a caution, which advises you to consult the
documentation where this symbol is marked.
CAUTION – Do not operate this product in a manner not specified in this document.
Product misuse can result in a hazard. You can compromise the safety protection built into
the product if the product is damaged in any way.

10

About this Manual

Related Information
Refer to the following documents for more information on using a TEMPpoint, VOLTpoint, or
MEASURpoint LXI instrument:• DtxMeasurement IVI-COM Driver online help. This document describes how to use the
IVI-COM driver to access the capabilities of your instrument.
The IVI-COM driver works with any development environment that supports COM
programming, including MATLAB® from The MathWorksTM, Microsoft® Visual C#®.NETor Visual Basic®.NET, Agilent® VEE Pro, National Instruments™ LabVIEW™ or
LabWindows™, and so on.
• QuickDAQ User’s Manual (UM-25242). This manual describes how to create a QuickDAQ
application to acquire and analyze data from a TEMPpoint, VOLTpoint, or MEASURpoint
instrument.
• SCPI Programmer’s Manual for LXI Measurement Instruments. For programmers who want
to use the SCPI interface to program a TEMPpoint, VOLTpoint, or MEASURpoint
instrument, this document describes the supported SCPI commands and example
programs for these instruments.
• IVI foundation (www.ivifoundation.org)• Omega Complete Temperature Measurement Handbook and Encyclopedia® or the Omega
Engineering web site: http://www.omega.com. Both resources provide valuable information on
thermocouple types, RTD types, standards, and linearization.

Where To Get Help
Should you run into problems installing or using a TEMPpoint, VOLTpoint, or MEASURpoint
instrument, the Data Translation Technical Support Department is available to provide
technical assistance. Refer to Chapter 7 for more information. If you are outside the UnitedStates or Canada, call your local distributor, whose number is listed on our web site(www.mccdaq.com).

11

About this Manual12

1Overview
Hardware Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Supported Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Getting Started Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

13

Chapter 1

Hardware Features
Data Translation provides a number of LXI (Ethernet) instruments to meet your measurement
needs, including the following:• TEMPpoint – a family of temperature measurement instruments• VOLTpoint – a family of voltage measurement instruments• MEASURpoint – a family of mixed temperature and voltage measurement instruments
All of these Ethernet instruments are class C devices that comply with LXI version 1.1.
The following sections summarize the features of the TEMPpoint, VOLTpoint, and
MEASURpoint LXI instruments.

TEMPpoint Features
TEMPpoint instruments include the following models: DT8871U, DT8871, and DT8872.
Figure 1 shows a DT8871U instrument.

Figure 1: TEMPpoint Instrument

The key features of TEMPpoint instruments are as follows:• DT8871U and DT8871:
 Configurable analog input channels for thermocouple or differential voltage inputs;
easy-access jacks for each channel for quick wiring
 One CJC (cold junction compensation) input for each thermocouple channel

14Overview B, E, J, K, N, R, S, and T thermocouple types supported; the instrument automaticallylinearizes the measurements and returns the data as a 32-bit, floating-pointtemperature values
 Input range of ±0.075 V for the DT8871U (with 0.25 V RMS A/D noise using nosoftware filtering) and ±1.25 V for the DT8871 (with 5 V RMS A/D noise using nosoftware filtering) Break-detection circuitry to detect open thermocouple inputs• DT8872:
 Configurable analog input channels for RTDs and differential voltage inputs;
easy-access jacks for each channel for quick wiring
 100 , 500 , and 1000  platinum RTD types supported using alpha curves of 0.00385(European) or 0.00392 (American)
 4-wire, 3-wire, or 2-wire configurations; the DT8872 automatically linearizes themeasurements and returns the data as 32-bit, floating-point temperature, resistance, orvoltage values
 Input range of ±1.25 V• One 24-bit, Delta-Sigma A/D converter per channel for simultaneous, high-resolution
measurements• Throughput rate of up to 10 Samples/s for all channels.
• Software or external, digital trigger on digital input line 0 starts acquisition• Auto-calibrating front-end resets the zero point on each power-up; in addition, theinstrument supports anytime calibration, performing an auto-calibration function on
software command• Measurement Instrument Calibration Utility allows you to calibrate the instrument in thefield (see page 21 for more information on this utility)• 8 opto-isolated digital input lines; you can read the digital input port through the analog
input data stream for correlating analog and digital measurements• 8 opto-isolated digital output lines; the outputs are solid-state relays that operate from±30 V at currents up to 400 mA (peak) AC or DC

15

Chapter 1

VOLTpoint Features
Figure 2 shows a VOLTpoint instrument.

Figure 2: VOLTpoint Instrument

The key features of VOLTpoint (DT8873) instruments are as follows:• Direct connection of analog input channels for differential voltage inputs; removablescrew terminal blocks for each channel for quick wiring• One 24-bit, Delta-Sigma A/D converter per channel for simultaneous, high-resolution
measurements• Software-selectable input range of ±10 V or ±60 V per channel (note that for the ±60 V
range, no more than 30 Vrms, 42.4 Vpk, 60 VDC is allowed)• Throughput rate of up to 10 Samples/s for all channels• Software or external, digital trigger on digital input line 0 starts acquisition• Auto-calibrating front-end resets the zero point on each power-up; in addition, theinstrument supports anytime calibration, performing an auto-calibration function on
software command• Measurement Instrument Calibration Utility allows you to calibrate the instrument in thefield (see page 21 for more information on this utility)• 8 opto-isolated digital input lines; you can read the digital input port through the analog
input data stream for correlating analog and digital measurements• 8 opto-isolated digital output lines; the outputs are solid-state relays that operate from±30 V at currents up to 400 mA (peak) AC or DC

16

Overview

MEASURpoint Features
The standard MEASURpoint (DT8874) instrument provides 16 thermocouple channels, 16
RTD channels, and 16 voltage channels. Figure 3 shows a MEASURpoint instrument.

Figure 3: MEASURpoint Instrument

The key features of MEASURpoint (DT8874) instruments are as follows:• Analog Input Channels 0 to 15:
 Configurable channels for thermocouple or differential voltage inputs; easy-accessjacks for each channel for quick wiring
 One CJC (cold junction compensation) input for each thermocouple channel
 B, E, J, K, N, R, S, and T thermocouple types supported; the instrument automaticallylinearizes the measurements and returns the data as a 32-bit, floating-pointtemperature values
 Input range of ±0.075 V (with 0.25 V RMS A/D noise using no software filtering) Break-detection circuitry to detect open thermocouple inputs

17Chapter 1• Analog Input Channels 16 to 31:
 Configurable analog input channels for RTDs and differential voltage inputs;
easy-access jacks for each channel for quick wiring
 100 , 500 , and 1000  platinum RTD types supported using alpha curves of 0.00385(European) or 0.00392 (American)
 4-wire, 3-wire, or 2-wire configurations; the DT8872 automatically linearizes themeasurements and returns the data as 32-bit, floating-point temperature, resistance, orvoltage values
 Input range of ±1.25 V• Analog Input Channels 31 to 48:
 Direct connection of analog input channels for differential voltage inputs; removablescrew terminal blocks for each channel for quick wiring
 Software-selectable input range of ±10 V or ±60 V per channel (note that for the ±60 V
range, no more than 30 Vrms, 42.4 Vpk, 60 VDC is allowed)• One 24-bit, Delta-Sigma A/D converter per channel for simultaneous, high-resolution
measurements• 30 VAC, 60 VDC continuous functional isolation ch-ch and ch-gnd, verified by a 500 Vpk
withstand• Throughput rate of up to 10 Samples/s for all channels• Software or external, digital trigger on digital input line 0 starts acquisition• Auto-calibrating front-end resets the zero point on each power-up; in addition, theinstrument supports anytime calibration, performing an auto-calibration function on
software command• Measurement Instrument Calibration Utility allows you to calibrate the instrument in thefield (see page 21 for more information on this utility)• 8 opto-isolated digital input lines; you can read the digital input port through the analog
input data stream for correlating analog and digital measurements• 8 opto-isolated digital output lines; the outputs are solid-state relays that operate from±30 V at currents up to 400 mA (peak) AC or DC

18

OverviewSupported Software
The following software is available for use with the TEMPpoint, VOLTpoint, and
MEASURpoint instruments:• Eureka Discovery Utility – This utility helps you locate or "discover" all LXI (Ethernet)
instruments that are connected to your system and provides the following information
about your instrument: the IP address, manufacturer, model number, serial number, andversion of the firmware that is running on your instrument. In addition, you can use thisutility to configure Windows firewall settings and update the firmware for your Data
Translation LXI instrument.
• Instrument Web Interface – This built-in interface, described in Chapter 5, allows you toverify the operation of your instrument and perform basic functions with Internet
Explorer and no additional software. Using it, you can configure your instrument, control
output signals, measure input signals, and save results to disk.
• QuickDAQ Base Version – The base version of QuickDAQ is free-of-charge and allows
you to acquire and analyze data from all Data Translation USB and Ethernet devices,
except the DT9841 Series, DT9817, DT9835, and DT9853/54. Using the base version of
QuickDAQ, you can perform the following functions: Discover and select your devices.
 Configure all input channel settings for the attached sensors.
 Load/save multiple hardware configurations.
 Generate output stimuli (fixed waveforms, swept sine waves, or noise signals).
 On each supported data acquisition device, acquire data from all channels supported
in the input channel list.
 Choose to acquire data continuously or for a specified duration.
 Choose software or triggered acquisition.
 Log acquired data to disk in an .hpf file.
 Display acquired data during acquisition in either a digital display using the Channel
Display window or as a waveform in the Channel Plot window.
 Choose linear or logarithmic scaling for the horizontal and vertical axes.
 View statistics about the acquired data, including the minimum, maximum, delta, andmean values and the standard deviation in the Statistics window.
 Export time data to a .csv or .txt file; you can open the recorded data in Microsoft
Excel® for further analysis.
 Read a previously recorded .hpf data file.
 Customize many aspects of the acquisition, display, and recording functions to suit
your needs, including the acquisition duration, sampling frequency, trigger settings,
filter type, and temperature units to use.

19

Chapter 1• QuickDAQ FFT Analysis Option – When enabled with a purchased license key, theQuickDAQ FFT Analysis option includes all the features of the QuickDAQ Base version
plus basic FFT analysis features, including the following: The ability to switch between the Data Logger time-based interface and the FFT
Analyzer block/average-based interface.
 Supports software, freerun, or triggered acquisition with accept and reject controls for
impact testing applications.
 Allows you to perform single-channel FFT (Fast Fourier Transform) operations,
including AutoSpectrum, Spectrum, and Power Spectral Density, on the acquired
analog input data. You can configure a number of parameters for the FFT, including
the FFT size, windowing type, averaging type, integration type, and so on.
 Allows you to display frequency-domain data as amplitude or phase.
 Supports dB or linear scaling with RMS (root mean squared), peak, and peak-to-peakscaling options
 Supports linear or exponential averaging with RMS, vector, and peak hold averaging
options.
 Supports windowed time channels.
 Supports the following response window types: Hanning, Hamming, Bartlett,Blackman, Blackman Harris, and Flat top.
 Supports the ability to lock the waveform output to the analysis frame time.
 Allows you to configure and view dynamic performance statistics, including the input
below full-scale (IBF), total harmonic distortion (THD), spurious free dynamic range(SFDR), signal-to-noise and distortion ratio (SINAD), signal-to-noise ratio (SNR), andthe effective number of bits (ENOB), for selected time-domain channels in the Statistics
window.
 Supports digital IIR (infinite impulse response) filters.
• QuickDAQ Advanced FFT Analysis Option – When enabled with a purchased software
license, the QuickDAQ Advanced FFT Analysis option includes all the features of the
QuickDAQ Base version with the FFT Analysis option plus advanced FFT analysis
features, including the following: Allows you to designate a channel as a Reference or Response channel.
 Allows you to perform two-channel FFT analysis functions, including Frequency
Response Functions (Inertance, Mobility, Compliance, Apparent Mass, Impedance,
Dynamic Stiffness, or custom FRF) with H1, H2, or H3 estimator types,
Cross-Spectrum, Cross Power Spectral Density, Coherence, and Coherent Output
Power.
 Supports the Exponential response window type.
 Supports the following reference window types: Hanning, Hamming, Bartlett,Blackman, Blackman Harris, FlatTop, Exponential, Force, and Cosine Taper windows.
 Supports real, imaginary, and Nyquist display functions.
 Allows you to save data in the .uff file format.

20

Overview• DtxMeasurement IVI-COM driver – This driver provides access to the instrument’s
functions through a COM server. The IVI-COM driver works in any 32- or 64-bit
development environment that supports COM programming, including MATLAB, Visual
Basic.NET, Visual C#.NET, Agilent VEE Pro, LabVIEW, LabWindows, and others.
• SCPI commands – Use SCPI commands to program TEMPpoint, VOLTpoint, or
MEASURpoint LXI instruments. Refer to the SCPI Programmer’s Manual for LXI
Measurement Instruments for information on the supported SCPI commands and example
programs.
• Measurement Instrument Calibration Utility – Users can calibrate a TEMPpoint,
VOLTpoint, or MEASURpoint instrument in the field using precise calibration equipment
and the Measurement Instrument Calibration Utility. Since each instrument consists of up
to 48 individual channels, great care must be taken to ensure that proper warm-up times
are followed and precise calibration equipment is used.
The calibration utility ships with a comprehensive help file that describes the required
equipment and calibration procedure, including warm-up times, for each instrument.
The calibration utility allows you to revert to the factory calibration for any or all
channels, or revert back to the last user calibration values, if desired. In addition, thisutility generates a report that lists the starting and ending calibration values for eachchannel, allowing traceability.
Refer to the Data Translation web site (www.mccdaq.com) for information about selecting theright software package for your needs.

21Chapter 1

Accessories
The following optional accessories are available for TEMPpoint, VOLTpoint, or
MEASURpoint instruments:• STP37 screw terminal panel – The STP37, shown in Figure 4, permits easy screw terminal
connections for accessing the digital I/O signals of a TEMPpoint, VOLTpoint, or
MEASURpoint instrument.

Figure 4: STP37 Screw Terminal Panel• EP333 cable–The EP333, shown in Figure 5, is a 2-meter shielded cable with two 37-pin
connectors that connects the STP37 screw terminal panel to the digital I/O connector of
the instrument.

Figure 5: EP333 Cable• EP373 Single Rack-mount Kit – Mounts one TEMPpoint, VOLTpoint, or MEASURpoint
instrument in a rack.
• EP374 Dual Rack-mount Kit – Mounts two TEMPpoint, VOLTpoint, or MEASURpoint
instruments side-by-side in a rack.

22

Overview

Getting Started Procedure
The flow diagram shown in Figure 6 illustrates the steps needed to get started using a
TEMPpoint, VOLTpoint, or MEASURpoint instrument. This diagram is repeated in each
Getting Started chapter; the shaded area in the diagram shows you where you are in thegetting started procedure.

Prepare to Use the Instrument(see Chapter 2 starting on page 27)
Set Up and Install the Instrument(see Chapter 3 starting on page 33)
Wire Signals(see Chapter 4 starting on page 45)

Verify the Operation of the Instrument(see Chapter 5 starting on page 67)

Figure 6: Getting Started Flow Diagram

23Chapter 1

24

Part 1: Getting Started

2
Preparing to Use theInstrument
Unpacking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Checking the System Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Installing the Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Viewing the Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

27

Chapter 2

Prepare to Use the Instrument(this chapter)

Set Up and Install the Instrument(see Chapter 3 starting on page 33)
Wire Signals(see Chapter 4 starting on page 45)

Configuring the Instrument Using the Web
Interface (see Chapter 5 starting on page 67)28

Preparing to Use the Instrument

UnpackingOpen the shipping box and verify that the following items are present:• TEMPpoint, VOLTpoint, or MEASURpoint instrument• EP372 Ethernet cable• EP361 +5V power supply and cable• For DT8872, DT8873, and DT8874 instruments, a bag of pluggable screw terminableblocks.
If an item is missing or damaged, contact Data Translation. If you are in the United States, callthe Customer Service Department at 508-946-5100. An application engineer will guide you
through the appropriate steps for replacing missing or damaged items. If you are locatedoutside the United States, call your local distributor, listed on Data Translation’s web site(www.mccdaq.com).

29

Chapter 2

Checking the System Requirements
For reliable operation, ensure that your computer meets the following system requirements:• Processor: Pentium 4/M or equivalent• RAM: 1 GB
• Screen Resolution: 1024 x 768 pixels• Disk Space: 4 GB
• Ethernet port
• Administrator privileges for software installation• For access to the instrument web interface: Java Version 6, Update 5 or greater Internet Explorer 6.0 or 7.0 web browser
Refer to page 69 for more information on installing Java and configuring your browser
settings• Acrobat Reader 5.0 or later for viewing documentation30

Preparing to Use the Instrument

Installing the SoftwareThis section describes how to install the software you need to use your TEMPpoint,
VOLTpoint, or MEASURpoint instrument.

Prerequisite Software
No prerequisite software is required if you are using a single client to access a TEMPpoint,
VOLTpoint, or MEASURpoint instrument on the LXI bus, or if you are managing how
multiple clients concurrently access the instrument on the LXI bus. (In these case, yourapplication can use sockets to communicate with the instrument.)
If, however, you want multiple clients to access your instrument on the LXI bus, and you want
to "lock" access to the instrument so that one client cannot change the configuration of the
instrument that another client is accessing, you need to install VISA; we recommend either
Agilent VISA or NI-VISA from National Instruments. You can then use the VISA methods
viLock/viUnlock to prevent other clients from accessing the instrument.
To install Agilent VISA, do the following:
1. Go to www.agilent.com, enter IO Libraries Suite in the search field, and select Agilent
IO Libraries Suite 15.0 from the search results.
2. Follow the instructions on Agilent’s web site to download and install the Agilent IO
Libraries, which include VISA support, VISA COM support, and the Agilent Connection
Expert tool.
We recommend that you run Data Translation’s Eureka Discovery Utility that is provided with
the MEASURpoint software to locate your LXI instrument on the network (see page 75 formore information).

Installation Instructions
Install the software for your instrument from the web at
http://mccdaq.com/downloads/DTSoftware/MEASURpoint.
The installation program guides you through the installation process.

31

Chapter 2

Viewing the Documentation
Note: To view the documentation, you must have Adobe Reader 5.0 or greater installed onyour system.

You can access the documentation for your instrument from the Windows Start menu asfollows:• For documentation about the TEMPpoint, VOLTpoint, or MEASURpoint instrument, click
Programs -> Data Translation, Inc -> Hardware Documentation -> User’s Manual forStandard TEMPoint, VOLTpoint, and MEASURpoint LXI Instruments.
• For documentation on the Eureka Discovery Utility, click Programs -> Data Translation,
Inc -> Instrument Support -> Eureka LXI Instrument Discovery.
• For documentation on the QuickDAQ application, click Programs -> Data Translation,
Inc -> QuickDAQ -> QuickDAQ User’s Manual• For documentation on the DtxMeasurement IVI-COM driver, click Programs -> Data
Translation, Inc -> DtxMeasurement -> DtxMeasurement IVI Driver 1.1.8
Documentation.
• For documentation about SCPI support, click Programs -> Data Translation, Inc ->Measurement SCPI Support ->SCPI Programmer’s Manual for Measurement.
The following may be helpful when using Adobe Reader:• To navigate to a specific section of the document, click a heading from the table of contentson the left side of the document.
• Within the document, click the text shown in blue to jump to the appropriate reference(the pointer changes from a hand to an index finger).
• To go back to the page from which the jump was made, click the right mouse button and
Go Back, or from the main menu, click Document, and then Go Back.
• To increase or decrease the size of the displayed document, from the main menu, click
View, and then Zoom.
• By default, Adobe Reader smooths text and monochrome images, sometimes resulting inblurry images. If you wish, you can turn smoothing off by clicking File, and thenPreferences/General, and unchecking Smooth Text and Images.

32

3
Setting Up and Installing
the Instrument
Connecting the Instrument to the LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Applying Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Getting an IP Address and Host Name. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Determining Ethernet Activity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Resetting the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44

33

Chapter 3

Prepare to Use the Instrument(see Chapter 2 starting on page 27)
Set Up and Install the Instrument(this chapter)

Wire Signals(see Chapter 4 starting on page 45)

Configuring the Instrument Using the Web
Interface (see Chapter 5 starting on page 67)

Note: Your TEMPpoint, VOLTpoint, and MEASURpoint instruments are factory-calibrated.
Thereafter, yearly recalibration is recommended. Refer to page 106 for more information on
calibration.

34

Setting Up and Installing the Instrument

Connecting the Instrument to the LAN
Figure 7 shows the LAN (RJ45) connector on the rear of the instrument that is used to connect
your instrument to the LAN (Local Area Network).

LAN
Connector

Figure 7: LAN Connector on the Rear of the Instrument

This section describes how to connect your instrument to the LAN. Two connection schemes
are shown:• Site LAN connections, described on page 36• Private LAN connections, described on page 37

Note: It is recommended that you consult with your network administrator to ensure that
all network security, performance, and reliability issues are considered when using
connecting instruments to the LAN.

35

Chapter 3

Connecting to a Site LAN
A site LAN is useful in applications that require access by many users or access by users at
distributed sites. In this connection scheme, a DHCP (Dynamic Host Configuration Protocol)server is used to assign an IP address to the instrument.
Figure 8 shows a typical site LAN connections using a dedicated Ethernet hub, switch, orrouter. Figure 9 shows typical site LAN connections without using a dedicated Ethernet hub,switch, or router.

Note: Use standard LAN cables for network connections. TEMPpoint, VOLTpoint, and
MEASURpoint instruments ship with a standard LAN cable (EP372) for connecting to the
LAN (RJ45) connector on the rear panel of the instrument.

ComputerEthernet
Hub/ Switch/ Router

TEMPpoint,
VOLTpoint, or
MEASURpoint

TEMPpoint,
VOLTpoint, or
MEASURpoint+5 V Power
Supply+5 V Power
SupplyTo Site LAN

TEMPpoint,
VOLTpoint, or
MEASURpoint

TEMPpoint,
VOLTpoint, or
MEASURpoint+5 V Power
Supply+5 V Power
SupplyFigure 8: Typical Site LAN Connections using a Hub, Switch, or Router36Setting Up and Installing the Instrument

To Site LAN

Computer

To Site LAN

TEMPpoint,
VOLTpoint, or
MEASURpoint+5 V Power
SupplyFigure 9: Typical Site LAN Connections Without Using a Hub, Switch, or Router

Connecting to a Private LAN
A private LAN (or subnet) generally involves the direct connection of the instruments to thecomputer, and may include Ethernet hubs or switches. Access to the instruments is limited tousers that are directly connected to the private LAN; therefore, security, performance, andreliably are generally better on a private LAN than on a site LAN.
In this connection scheme, the DHCP (Dynamic Host Configuration Protocol) server istypically not available; therefore, Auto-IP is used to assign an IP address to the instrument.

Note: If no DHCP server exists and your PC is set up to use a static IP address, you must
temporarily reconfigure your PC to use Auto-IP, as described on Appendix C starting on
page 145.

Connecting Using a Hub or Switch
Figure 10 shows a typical connection scheme when connecting TEMPpoint, VOLTpoint, or
MEASURpoint instruments to a private LAN using a dedicated Ethernet hub or switch.

Note: Use standard LAN cables for network connections. The instrument ships with astandard LAN cable (EP372) for connecting to the LAN (RJ45) connector on the rear panel ofthe instrument.

37

Chapter 3

ComputerEthernet
Hub/ Switch

TEMPpoint,
VOLTpoint, or
MEASURpoint

TEMPpoint,
VOLTpoint, or
MEASURpoint+5 V Power
Supply+5 V Power
SupplyTEMPpoint,
VOLTpoint, or
MEASURpoint

TEMPpoint,
VOLTpoint, or
MEASURpoint+5 V Power
Supply+5 V Power
SupplyFigure 10: Typical Private LAN Connections using a Hub or Switch

Connecting Directly to a Computer
Optionally, you can connect the TEMPpoint, VOLTpoint, or MEASURpoint instrument
directly to your computer, creating an ad hoc network, as shown in Figure 11. Be aware thatthe time and date settings of the instrument will not be updated using this connection method.
Therefore, this connection scheme is generally recommended for quick set up and verification
only.

Note: TEMPpoint, VOLTpoint, and MEASURpoint instruments do not support the
Auto-MDIX function; therefore, use a crossover cable rather than a standard LAN cable toconnect your instrument unless your computer has enabled the Auto-MDIX function.

Computer

TEMPpoint,
VOLTpoint, or
MEASURpoint
Standard LAN Cable (if PC enabled Auto-MDIX)
or
Ethernet Crossover Cable (if PC doesn’t enableAuto-MDIX or you are not sure)+5 V Power
SupplyFigure 11: Typical Private LAN Connections when Connecting Directly to a Computer

38Setting Up and Installing the Instrument

Applying Power
TEMPpoint, VOLTpoint, and MEASURpoint instruments are shipped with an EP361 +5V
power supply and cable. To apply power to the instrument, do the following:
1. Connect the +5 V power supply to the power connector on the rear panel of the
instrument. Refer to Figure 12.

EP361 +5 V
Power Supply

Power
SwitchFigure 12: Attaching a +5 V Power Supply to the Instrument

2. Plug the power supply into a wall outlet.

Note: For proper grounding of your measurement instrument, ensure that you use thepower supply and cable (EP361) that is provided with the instrument and that you use all
three prongs of the cable when connecting it to your wall outlet.

3. Press the Power switch on the rear panel of the instrument, shown in Figure 12, to turn on
the instrument.
The Power LED on the front panel lights to indicate that power is on.

39

Chapter 3
Figure 13 shows the location of the LEDs on the front panel of the instrument; a
MEASURpoint instrument is shown in this example.

Power LED

LAN LED

Figure 13: LEDs on the Front Panel of the Instrument

40

Setting Up and Installing the Instrument

Getting an IP Address and Host Name
Once your instrument is connected to the LAN and powered on, the instrument automaticallyrequests an Ethernet address from a DHCP (Dynamic Host Configuration Protocol) server, if
available, and a host name from a DNS (Dynamic Domain Name Service) server, if available.
If these services are not available on the LAN, the instrument uses Auto-IP to set up its
TCP/IP configuration. In this case, the IP address is in the range of 169.254.0.0 to
169.254.255.255 with a subnet mask of 255.255.0.0.

Note: If no DHCP server exists and your PC is set up to use a static IP address, you must
temporarily reconfigure your PC to use Auto-IP, then configure your instrument to use astatic IP address, as described in Appendix C starting on page 145.

You can use the instrument’s web interface, described in Chapter 5 starting on page 67, to see
the IP address and host name that is assigned to your instrument.

Notes: When programming a TEMPpoint, VOLTpoint, or MEASURpoint instrument, youaccess the instrument through its address string, which consists of an IP address or hostname, such as TCPIP0::192.43.218.69::inst0::INSTR or TCPIP0::192.43.218.69::SOCKET. If ahost name was returned by the DNS server, you can also address the instrument using its
host name, such as TCPIP0::arrakis.datx.com::inst0::INSTR.
For IVI-COM programmers, you can also assign a VISA alias to the instrument. For example,
rather than addressing the instrument as TCPIP0::192.43.218.69::inst0::INSTR, you can a
VISA alias, such as TEMPpoint1, instead. See your VISA documentation for more
information on VISA resource strings and creating VISA aliases.

41

Chapter 3

Determining Ethernet Activity
You can use the ENet Link and ENet Activity LEDs on the rear of the instrument, shown in
Figure 14, with the LAN LED on the front of the instrument, shown in Figure 13, to determine
the Ethernet activity on your instrument. Table 1 describes the meaning of these LEDs.

ENet Link
LED

ENet Activity
LED

USB LED (not used on this instrument)
LMT LED
OPN LED

Reset Pin

Figure 14: Rear Panel of the Instrument

Table 1: Using LEDs to Determine Ethernet Activity
LEDs
LAN LED(on front panel)

Color

Description

Solid Green

Instrument has valid IP address.

Blinking Green

Instrument identified using the Web interface; see page 75
for more information.

Red

If the Ethernet link is operational, the instrument does nothave a valid IP address.
Otherwise, the Ethernet link is not operational.

42

Setting Up and Installing the Instrument
Table 1: Using LEDs to Determine Ethernet Activity (cont.)
LEDs

Color

Description

ENet Link LED(on rear panel)

Yellow

Ethernet link operational.

Off

Ethernet link not operational.

ENet Activity LED(on rear panel)

Green

Network traffic detected.

Off

No network traffic detected.

43Chapter 3

Resetting the Instrument
If needed, you can restore the default configuration of your instrument by pressing the Resetpin on the rear panel of the instrument, shown in Figure 14 on page 42, until the LAN LED on
the front panel turns off (which takes approximately 5 seconds), and then releasing the Resetpin.
The instrument reboots automatically using the factory-default LAN configuration (DHCP
and auto-IP enabled); this process typically takes up to 40 seconds to complete. This forces the
instrument to re-acquire an IP address from the DHCP server, or if that fails, to use Auto-IP to
get an IP address.

Note: The default configuration overwrites any changes that you have made to the LAN
configuration (IP address and password) using the instrument’s web interface. Refer to page
79 for information on the default values that are used when the instrument is reset.
The calibration parameters are not affected by the reset.

44

4
Wiring Signals
General Wiring Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Warm-Up Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Connecting Thermocouple Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Connecting RTD Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Connecting Voltage Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Connecting Current Loop Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Connecting Digital I/O Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64

45

Chapter 4

Prepare to Use the Instrument(see Chapter 2 starting on page 27)
Set Up and Install the Instrument(see Chapter 3 starting on page 33)

Wire Signals(this chapter)

Configuring the Instrument Using the Web
Interface (see Chapter 5 starting on page 67)

46

Wiring Signals

General Wiring Recommendations
Keep the following recommendations in mind when wiring signals to a TEMPpoint,
VOLTpoint, or MEASURpoint instrument:• Separate power and signal lines by using physically different wiring paths or conduits.
• To avoid noise, do not locate the instrument and cabling next to sources that produce highelectromagnetic fields, such as large electric motors, power lines, solenoids, and electricarcs, unless the signals are enclosed in a mumetal shield.
• Locate the instrument’s front panel as far away as possible from sources of high or low
temperatures or strong air currents, such as fans.
• Prevent electrostatic discharge to the I/O while the instrument is operational.
• When wiring thermocouples, select an appropriate wire length and gauge for eachthermocouple; in general, use the shortest wire length and largest gauge for theapplication to yield best results.
• Use shielded wire for maximum rejection of electrical interference.

47

Chapter 4

Warm-Up TimeFor accurate thermocouple measurements, MEASURpoint instruments require a warm-up
time of 1 hour for the analog circuitry to stabilize.
For accurate RTD measurements, ensure that your RTD sensors and external calibration
resistors warm up for 1 minute after the MEASURpoint instrument has been warmed up for 1
hour.

48

Wiring Signals

Connecting Thermocouple Inputs
The DT8871U, DT8871, and DT8874 instruments contain thermocouple jacks for connecting
thermocouple inputs.

Note: On the standard DT8874 instrument, channels 0 to 15 correspond to the thermocouple
input channels.

Internally, these signals are connected in differential mode. You can mix and match thefollowing thermocouple types across channels: B, E, J, K, N, R, S, and/or T.
Each thermocouple input jack is polarized and accepts a mating plug in the appropriateorientation. Table 2 lists the color designations for the + and – polarities of the supported
thermocouple types for both the ANSI (American) and IEC (International) standards.

Table 2: Thermocouple Color Designation Standards
Thermocouple
Standard

Thermocouple
Type

Wire Color Coding+ Polarity

Wire Color Coding– Polarity

ANSI

Type JWhiteRedType K

Yellow

Red

Type T

Blue

Red

Type E

VioletRed

Type SBlack

RedType R

Black

Red

Type B

Gray

Red

Type N

OrangeRed

Type J

Black

White

Type K

Green

White

Type T

Brown

White

Type E

VioletWhite

Type S

OrangeWhite

Type R

OrangeWhite

Type B

Gray

White

Type N

Pink

White

IEC

For more information on thermocouple standards, refer to the following web site:
http://www.omega.com/thermocouples.html.

49

Chapter 4

CAUTION:
When connecting inputs to the thermocouple connectors on a
MEASURpoint or TEMPpoint instrument, it is highly recommended
that you use only original Omega thermocouple plugs (SMPW), as
connectors from other suppliers may not be equivalent mechanically.
Refer to page 138 for more information on the connectors.
If you use connectors from suppliers other than Omega, there is arisk that you may mechanically damage the thermocouple
connectors on the MEASURpoint or TEMPpoint instrument.

Figure 15 shows how to connect a thermocouple input to a thermocouple channel.

–+

Thermocouple
Channels

Omega Plug (SMPW)+–

Thermocouple Input

Figure 15: Connecting Thermocouple Inputs

50Wiring Signals

Connecting RTD Inputs
Each DT8872 and DT8874 contains pluggable screw terminals for connecting RTD inputs.
Internally, these signals are connected in differential mode.

Note: On the standard DT8874 instrument, channels 16 to 31 correspond to the RTD input
channels.

Figure 16 shows the numbering of the screw terminal blocks for RTD connections.

RTD
Channels

432
Return – Sense +Sense

1
Current

Figure 16: Screw Terminal Block Numbering for RTD Connections

51

Chapter 4
The DT8872 supplies each RTD channel with 425 A of excitation current to prevent
self-heating. The resistance of the RTD circuit increases gradually, repeatably, and linearlywith temperature. As the resistance increases, the voltage drop across the RTD also increases.
The DT8872 reads this voltage drop and automatically converts the voltage to the appropriate
temperature based on the RTD type.
The DT8872 and DT8874 support Pt100 (100  Platinum), Pt500 (500  Platinum), and Pt1000(1000  Platinum) RTD types using Alpha coefficients of 0.00385 and 0.00392; you can mix andmatch RTD types across RTD channels. Refer to the following web site for more information
on RTD types: http://www.omega.com.
To connect an RTD input, you can use a 4-wire, 3-wire, or 2-wire connection scheme, describedin the following subsections. For the best accuracy, use 4-wire RTD connections; thisconnection scheme enables Kelvin sensing to minimize errors due to lead wire resistance.

4-Wire RTD Connections
The 4-wire configuration offers the best accuracy with long connection wires, compared to the3- and 2-wire configurations. The 4-wire connection scheme eliminates errors due to lead wire
resistance (RL) and thermal heating. Wire impedance of up to 100  anywhere in the hookup
is automatically cancelled as long as the sense wires are connected.
Figure 17 shows a 4-wire RTD connection.

RTD Channel
425 A
Current

Return– Sense4

RL+Sense

3

RL

2

1

RL

RL

RTD

Figure 17: 4-Wire RTD Connection52

Wiring Signals

3-Wire RTD Connections
The 3-wire configuration eliminates one wire from the 4-wire RTD connection. Lead wire
resistance (RL) errors in the return wire from –Sense may be introduced unless the voltage
drop is essentially equal and opposite to the voltage drop across +Sense.
Figure 18 shows a 3-wire RTD connection.

RTD Channel
425 A
Current

Return– Sense+Sense

3

2

4

1

RL

RTD

*RL is lead wire resistance.

Figure 18: 3-Wire RTD Connection

2-Wire RTD Connections
The 2-wire configuration is the least accurate of the RTD wiring configurations because thelead wire resistance (RL) and its variation with temperature contribute significant
measurement errors, particularly if the lead wire is long. If you decide to use the 2-wireconnection scheme, ensure that you use short lead wire connections.
For example, if the lead resistance is 0.5  in each wire, the lead resistance adds a 1  of error
to the resistance measurement. Using a 100  RTD (Pt100) with a 0.00385/°C European curvecoefficient, the resistance represents an initial error of 1  /(0.385 /°C) or 2.6°C. Since thelead wire resistance changes with ambient temperature, additional errors are also introducedin the measurement.

53

Chapter 4
Figure 19 shows a 2-wire RTD connection.

RTD Channel

425 A
Current

Return– Sense4+Sense
3

RL

2

1

RL

RTD

Figure 19: 2-Wire RTD Connection

54Wiring Signals

Connecting Voltage Inputs
The way you connect voltage inputs depends on the channel type you are using. This section
describes how to connect voltage inputs to thermocouple input channels, RTD input channels,
and voltage input channels.

Connecting Voltage Inputs to Thermocouple Channels
Figure 20 shows how to connect a differential voltage input to a thermocouple input channelon the DT8871U, DT8871, or DT8874 instrument.

Note: On the standard DT8874 instrument, channels 0 to 15 correspond to the thermocouple
input channels.

55

Chapter 4–+

Thermocouple
Channels

Omega Plug (SMPW-U-M)

Voltage Input

Analog Input 0
Return–Analog Input 0+

Signal Source

Figure 20: Connecting Voltage Inputs to a Thermocouple Channel

56Wiring Signals

Connecting Voltage Inputs to RTD Channels
Figure 21 shows how to connect a voltage input to an RTD channel on a DT8872 or DT8874
instrument.

Note: On the standard DT8874 instrument, channels 16 to 31 correspond to the RTD input
channels.

RTD Channel– Sense4+Sense3

2

1

Shield

Vin –

Vin +

Figure 21: Connecting Voltage Inputs to an RTD Channel

The input impedance is well over 100 M using the voltage –Sense and +Sense inputs.
For best accuracy when connecting voltage inputs, use twisted-pair wires with a dead-ended
shield connected to pin 4 of the screw terminal block.

57

Chapter 4

Connecting Voltage Inputs to Voltage Channels
Each DT8873 and DT8874 contains pluggable screw terminals for connecting voltage inputs.

Note: On the standard DT8874 instrument, channels 32 to 47 correspond to the voltage input
channels.

Figure 22 shows the numbering of the screw terminal blocks for voltage connections.

Voltage Input
Channels43
Shield –Sense

2
1
No+SenseConnect

Figure 22: Screw Terminal Block Numbering for Voltage Connections

58

Wiring Signals
Figure 23 shows how to connect voltage inputs to the DT8873 and DT8874.

Voltage Channel– Sense4+Sense3

2

1

Shield
Vin –

Vin +

*Pin 2 is no connect

Figure 23: Connecting Voltage Inputs

The input impedance is well over 100 M using the voltage –Sense and +Sense inputs.

Note: For best accuracy when connecting voltage inputs, use twisted-pair wires with adead-ended shield connected to pin 4 of the screw terminal block.

59

Chapter 4

Connecting Current Loop Inputs
In some applications, such as solar cell, fuel cell, and car battery testing applications, you may
want to accurately sense and measure current in a high voltage loop.
TEMPpoint, VOLTpoint, and MEASURpoint instruments provide channel-to-channel
functional isolation of 60 VDC maximum continuous working voltage, meaning that each
input can be referenced to 60 VDC maximum, with a 500 Vpk withstand rating, verified by a
5 s dielectric withstand test.
The way you connect current loop inputs depends on the channel type you are using. Thissection describes how to connect current loop inputs to thermocouple input channels, RTD
input channels, and voltage input channels.

Connecting Current Loop Inputs to Thermocouple Channels
Thermocouple input channels on the DT8871U and DT8874 have an input range of ±0.075 V.
Therefore, you can use a 1  series resistor to measure ±0.075 A. Similarly, you can use a 0.1 series resistor to measure ±0.75 A.
Thermocouple input channels on the DT8871 have an input range of ±1.25 V. Therefore, you
can use a 1  series resistor to measure ±1.25 A. Similarly, you can use a 0.1  series resistor tomeasure ±12.5 A or a 10  series resistor to measure ±0.125 A.
Figure 24 shows how to wire your signals to measure a current loop. In this example, the input
is referenced to ±60 V.

Note: On the standard DT8874 instrument, channels 0 to 15 correspond to the thermocouple
input channels.

60

Wiring Signals

Thermocouple
Channels–+

1 series resistor+
60 V

Circuit+–

Use a 1  series resistor to convert current to voltage.
For thermocouple channels on the DT8871U and DT8874, 1 = 0.075 A = 0.075 V.
For thermocouple channels on the DT8871, 1 = 1.25 A = 1.25 V.

Figure 24: Connecting Current Loop Inputs to Thermocouple Channels

61

Chapter 4

Connecting Current Loop Inputs to RTD Channels
RTD channels on the DT8872 and DT8874 instruments have an input range of ±1.25 V.
Therefore, you can use a 1  shunt resistor to measure ±1.25 A. Similarly, you can use a 0.1 shunt resistor to measure ±12.5 A or a 10  shunt resistor to measure ±0.125 A.
Figure 25 shows how to wire your signals to measure a current loop. In this example, the input
is referenced to ±60 V.

Note: On the standard DT8874 instrument, channels 16 to 31 correspond to the RTD input
channels.

RTD Channel– Sense4+Sense3

2

1

Shield1 shunt resistor
Circuit++
60 V–

Use a 1  shunt resistor to convert current to voltage: 1 = 1.25 A = 1.25 V.

Figure 25: Connecting Current Loop Inputs to RTD Channels

62

Wiring Signals

Connecting Current Loop Inputs to Voltage Channels
Voltage input channels on the DT8873 and DT8874 instruments have an input range of ±10 V
or ±60 V. You select the input range for each channel using software.
With the 24-bit A/D converter, high current, high side current shunts can be used for
resolutions of less than 0.01 A on a 100 A range.
Typical Shunts:• Vishay WSMS5515.2 mV• Vishay CSM2512S
10 mV• Deltec MUB-500-50.1 mV

Notes: On the DT8874 instrument, channels 32 to 47 correspond to the voltage input
channels.

Figure 26 shows an example of wiring signals to measure ±20 mA using the ±10 V input
range.

Voltage Channel– Sense4

3+Sense2

1

Shield±20 mALoad

250 shunt resistor+
28 V (can be up to ±60 V)–

In this example, the input range is ±10 V.

Figure 26: Connecting a Current Loop Input to a Voltage Channel to Measure ±20 mA

63

Chapter 4

Connecting Digital I/O Signals
To make digital I/O connections easier, you can use the optional STP37 screw terminal panel
and EP333 cable with your TEMPpoint, VOLTpoint, or MEASURpoint instrument. Connect
the STP37 to the digital I/O connector of the instrument as shown in Figure 27:

Digital I/O
Connector

EP333 Cable

STP37 Screw Terminal Panel

Figure 27: Connecting the Instrument to the STP37

Figure 28 shows the layout of the STP37 screw terminal panel and lists the assignments ofeach screw terminal.

64

Wiring Signals

J1

Digital Input 1+ 2
Digital Input 1 21
Digital Input 2+ 3

17 Digital Output 7

Digital Input 4+ 5
Digital Input 4 24

Not Connected

Digital Input 3 23

Not Connected

Digital Input 3+ 4

Not Connected

TB2

20 18 19 37
Digital Input 0

1
Digital Input 0+

Digital Input 2 22

36 Digital Output 7

TB1

35 Digital Output 6
TB3

16 Digital Output 6
34 Digital Output 5
15 Digital Output 5
33 Digital Output 4
14 Digital Output 4

Digital Input 5+ 6
Digital Input 5 25

32 Digital Output 3
13 Digital Output 3

Digital Input 6+ 7

31 Digital Output 2

Digital Input 6 26
Digital Input 7+ 8

TB4

TB5

12 Digital Output 2
30 Digital Output 1

Digital Input 7 27

11 Digital Output 1

Not Connected

929 Digital Output 0

Not Connected 28

10 Digital Output 0

Figure 28: STP37 Screw Terminal Panel

Connecting Digital Input Signals
Figure 29 shows how to connect digital input signals (lines 0 and 1, in this case) to the digital
I/O connector on the TEMPpoint, VOLTpoint, or MEASURpoint instrument.

+5 V*
Instrument
Digital I/O Connector
pin 1

1 k*

DIN 0 +TTL Outputs

pin 2
pin 20

DIN 1 +

DIN 0 –

pin 21
DIN 1 –

*1 k pull-up to +5 V required for TTL outputs.

Figure 29: Connecting Digital Inputs

65

Chapter 4

Connecting Digital Output Signals
The digital output lines of a TEMPpoint, VOLTpoint, or MEASURpoint instrument act assolid-state relays. The customer-supplied signal can be ±30 V at up to 400 mA (peak) AC orDC.
You can use the digital output lines of the instrument to control solid-state or mechanicalrelays or high-current electric motors. Figure 30 shows how to connect digital output signals
to line 0 of the instrument to control a motor relay.

Motor

Instrument
Digital I/O Connector
Relay

Controlled by
Software10 A
Fuse
pin 10Digital Out 0Hot

pin 29Neutral120 V ACor 240 V AC

Digital Out 0–+*30V DC @ 400 mA*Output can switch AC or DC.
Note: Relay, motor, and circuits must be properly rated. Reinforced isolation must be
maintained between the digital output circuits and the relay/motor switching circuits.

Figure 30: Switching up to 30 V at 400 mA

66

5Configuring the Instrument
Using the Web Interface
Before Using the Web Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Locating Your Instrument on the LAN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Configuring the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Measuring Data and Controlling the Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Downloading Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

67

Chapter 5

Prepare to Use the Instrument(see Chapter 2 starting on page 27)
Set Up and Install the Instrument(see Chapter 3 starting on page 33)

Wire Signals(see Chapter 4 starting on page 45)

Configure the Instrument Using the Web
Interface (this chapter)

You can configure the operation of your instrument either locally or remotely using the
instrument’s web interface.
If your browser supports Java, you can also verify the operation of your instrument using the
web interface.
The QuickDAQ application that is provided as part of the MEASURpoint software also allows
you to verify the operation of your instrument and does not require Java for operation;
therefore, if your browser does not support Java, use QuickDAQ instead. Refer to the
documentation provided with QuickDAQ for more information.
This chapter focuses on configuring your instrument using the web interface.

Note: DT8871, DT8871U, DT8872, and DT8873 instruments with firmware version 2.2.3.1 orgreater are identified in firmware as DT8874-xxT-xxR-xxV, where xxT specifies the number ofthermocouple channels, xxR specifies the number of RTD channels, and xxV specifies thenumber of voltage input channels.

68

Configuring the Instrument Using the Web Interface

Before Using the Web Interface
This section describes system requirements and browser settings for proper operation of the
instrument’s web interface.

Note: At any instant, up to 8 clients can access the instrument concurrently using the webinterface.
Up to 12 additional clients can access the instrument concurrently using SCPI commands
over VISA or sockets. Of these, 4 can be VXI-11 clients, which use the ::SOCKETS or
VISA::INSTR resource to access the instrument.
At this time, the web and SCPI interfaces cannot be "locked;" therefore, one client can change
the configuration of the instrument that another client is accessing. However, you canoptionally lock the VXI-11 interface using the VISA APIs viLock/viUnlock; this prevents
other VXI-11 clients (including VXI-11 discovery) from accessing the instrument. Refer to the
SCPI documentation for your instrument for more information on supported SCPI
commands.

Java Requirements
To verify the operation of your instrument through the web interface, your browser must
support Version 6, Update 5 or greater of Java. If your browser does not support Java, you canstill configure your instrument through the web interface; however, you must use QuickDAQ
to verify the operation of your instrument in this case.
You can verify Java versions and settings by accessing the Java Control Panel, select Windows
Start -> Control Panel and open the Java dialog. To download or upgrade Java, go towww.java.com.

Internet Explorer Browser Settings
If you have an older version of Internet explorer that supports Java, configure your browser asfollows; otherwise, skip this section:• JavaScript (Active Scripting) must be enabled• Security level of the instrument’s IP address must be Medium-high or lower• Pop-up blockers must be disabled
The following sections describe how to configure these settings.

69

Chapter 5

JavaScript
To enable JavaScript (also referred to as Active Scripting), perform the following steps:
1. From the Internet Explorer browser, select Tools -> Internet Options.
2. Click the Security tab.
3. Select Internet, and then click Custom Level.
4. Scroll down to the Scripting section.

5. Under Active Scripting, select Enable, and then click OK.

Security Levels
By default, the IP address of the instrument is added to the Internet zone. If you'd rather leave
the settings of the Internet zone at a level higher than Medium-high, then you can add the IP
address of the instrument to either the Local intranet or Trusted sites zone and configure thesecurity level of that zone to Medium-high or lower.
The following section describe how to configure each zone.
Internet Zone
To configure the security level of the instrument module’s IP address in the Internet zone,
perform the following steps:
1. From the Internet Explorer browser, select Tools -> Internet Options.
2. Click the Security tab.

70

Configuring the Instrument Using the Web Interface

3. Select Internet and move the slide bar to select a security level of Medium-high or lower.
4. Click OK.
Local Intranet Zone
To add the IP address of the instrument to the Local intranet zone and configure its security
level, do the following:
1. From the Internet Explorer browser, select Tools -> Internet Options.
2. Click the Security tab.
3. Click Local intranet, and click Sites.
4. Select which web sites to add to the zone, and then click Advanced.
5. Enter the IP address of the instrument to the zone, and click Add.

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Chapter 5

6. Click Close.
7. Move the slide bar to select a security level of Medium-high or lower.
8. Click OK.
Trusted Sites Zone
To add the instrument’s IP address to the Trusted sites zone and configure its security level,
do the following:
To add the IP address of the instrument to the Trusted sites zone and configure its security
level, do the following:
1. From the Internet Explorer browser, select Tools -> Internet Options.
2. Click the Security tab.
3. Click Trusted sites, and click Sites.
4. Enter the IP address of the instrument to the zone (note that the address must be prefacedby (https://), and click Add.

72

Configuring the Instrument Using the Web Interface

5. Click Close.
6. Move the slide bar to select a security level of Medium-high or lower.
7. Click OK.

Pop-up Blockers
To disable pop-up blockers, perform the following steps:
1. From the Internet Explorer browser, select Tools ->Pop-up Blocker.
2. Select Turn Off Pop-up Blocker.

73

Chapter 5

Associating CSV Files with Microsoft Excel or Notepad
Note: This section applies only if your browser supports Java. If your browser does notsupport Java, downloading data to a file through the web interface is not supported.

If files with the .CSV extension do not have the proper file associations/actions set up, thenclicking Download in the Download Measurements page of the instrument web interface will
not present the option of saving the data to a file or loading the data to an application, such as
Microsoft Excel® or Microsoft® Notepad, that can display it. Instead, the data will be
displayed in the browser.
The following steps describe how to associate a CSV file with Microsoft Excel or Notepad in
Windows XP; refer to the documentation for your operating system for more information:
1. From the Windows Control Panel, open the Folder Options dialog, and select File Types.
2. Scroll down to the CSV entry and select it. (If it is not in the list add it as a new file type by
selecting New and entering CSV).
3. Click Advanced to access the Edit File Type dialog box.
4. Click New to access the New Action dialog box.
5. Enter Open in the Action: edit field.
6. Click Browse and find Excel.exe (typically located in C:\Program Files\Microsoft
Office\OFFICExx\EXCEL.EXE) or Notepad.exe (typically located in
C:\Windows\Notepad.exe) on your system, and then click OK.

7. Click OK.
Now when you click Download on the Download Measurements web page, you should see a
dialog box asking if you want to Open or Save the data in the appropriate application.

74

Configuring the Instrument Using the Web Interface

Locating Your Instrument on the LAN
To access the web interface of your instrument, you must determine its IP address on your
TCP/IP network.

Note: Discovery works only for devices on the same subnet.

We recommend that you run Data Translation’s Eureka Discovery Utility that is provided with
the instrument to locate your instrument on the network quickly. Alternatively, you can use
other LXI discovery tools, such as Agilent Connection Expert, if you have them installed onyour computer. Or you can check your router’s address assignments or locate the instrument’s
MAC (Ethernet hardware) address in your DHCP server log.

Running the Eureka Discovery Utility
To use the Eureka Discovery Utility, from the Windows Start menu, click Programs -> Data
Translation, Inc -> Instrument Support -> Eureka LXI Instrument Discovery.
A screen similar to the one shown in Figure 31 appears.

Figure 31: Eureka LXI Discovery Utility

If you are having trouble seeing your instrument in this list, check your Windows firewall
settings using the information in the next section; otherwise, skip this section and continue
with “Launching the Web Interface” on page 78.

75

Chapter 5

Configuring Windows Firewall Settings
If you are having trouble seeing your instrument using the Eureka Discovery Utility, checkyour Windows firewall settings by doing the following:
1. Right click in the tile bar of the Eureka Discovery Utility.
The following menu options appear:

2. Click the Firewall Configuration... option.
The following window appears:

76Configuring the Instrument Using the Web Interface

3. On the left side of the window, select Turn Windows Firewall on or off, select Turn On
Windows Firewall setting for proper operation of the Eureka Discovery Utility, and clickOK.
4. On the left side of the window, select Allow a program or feature through Windows
Firewall, ensure that Eureka LXI Instrument Discovery is included in the list of
exceptions, and click OK.
5. If Eureka LXI Instrument Discovery is not included in the exception list, add the utility to
the list of exceptions by doing the following:a. Click Allow another program...
b. Browse to C:\Program Files\Data Translation\Instrument Support\Eureka.exe,
and click Open.
The Eureka LXI Instrument Discovery utility appears in the window.
c.

Click Add to add the utility to the list of exceptions.

d. Click OK to exit from the Windows Firewall Configuration menu.

77Chapter 5

Launching the Web Interface
From the Eureka utility, double-click the appropriate IP address to open the web pages foryour instrument using your default web browser. Alternatively, you can enter the IP addressof your instrument directly in your Internet Explorer address bar to see the instrument’s web
interface.
The main web page, similar to the following screen, shows information about your instrumenton the network:

Note: If your browser does not support Java, the Measurement & control -> Acquisition
and Measurement & control -> Digital input pages of the web interface are not supported.
To acquire and view input data, use the QuickDAQ application instead.

If you have multiple instruments connected to the network, you can click "Turn ON front
panel identification indicator" to light the LAN LED on the instrument, described on page 40,
to indicate the device you are using.
To change the description, IP address, or time source associated with the instrument, click the
Modify links to navigate to the LAN Configuration page, described on page 79.

78

Configuring the Instrument Using the Web Interface

Configuring the Instrument
Web pages are provided for configuring the following aspects of your instrument:• Local Area Network (LAN) settings• Channels that you want to measure• Scan rate
• Filter• Alarm limits• Digital I/O lines

LAN Configuration
Use the Configuration -> LAN web page to configure the Local Area Network (LAN) settings
for the instrument. A screen similar to the following appears:

When you first access your instrument, the LAN settings that the instrument obtained
through DHCP or AutoIP should be sufficient. If you need to make changes later, click the
Modify button to enable changes. Contact your system administrator and view the
instrument’s built-in help pages to determine the correct LAN settings.

79

Chapter 5

Note: If you want to assign a static IP address, ensure that you uncheck the checkbox called
Automatic private IP address enabled.

When you click Modify, you must supply a password for the instrument.
The username is admin; it cannot be changed. The default password is admin. You can change
the password on this page.
Note that the new password is saved in permanent memory in the instrument and goes into
effect after the instrument reboots. If you are prompted for a password before the instrument
reboots, you must enter your original password. The web interface, IVI-COM driver, and SCPI
interface use the same password. You can also configure the password using the IVI-COM
driver or through SCPI commands.
You are prompted for this password any time the instrument’s configuration is changed orwhen an attempt is made to start or stop a scan. This mechanism relies on features in the
HTTP standard to prevent unauthorized users from reconfiguring or operating the
instrument. Note, however, that authentication is not required to view the instrument’s
configuration or scan results.

Note: The DT8871, DT8871U, DT8872, DT8873, and DT8874 instruments with firmware
version 2.2.3.1 or greater use the default user name admin and the default password admin.
Firmware version 2.2.3.1 and greater support password-protected commands. Therefore, youmust enter the appropriate password to change the instrument’s configuration or to start andstop a scan.
If the firmware version for these instruments is less than 2.2.3.1, then the default user name issysadmin and the default password is user. Firmware versions less than 2.2.3.1 do notsupport password-protected commands. Therefore, you are not prompted to enter apassword to change the instrument’s configuration or to start or stop a scan.

Specify the time zone that is used by the instrument as an offset (either + or –) from GMT(Greenwich Mean Time). The specified hour and minute is added to the UTC (Coordinated
Universal Time) time that is maintained by the instrument. For example choosing –5 hours, 0minutes sets the current time zone used by the instrument to five hours and 0 minutes behind
GMT.

Channel Configuration
Use the Configuration -> Channel web page to enable the channels that you want to measure,specify the sensor to use for each channel, and add a label to describe each channel, if desired.
A screen similar to the following appears:

80Configuring the Instrument Using the Web Interface

To change your channel configuration, do the following:
1. Under Enable Channel, check the boxes next to the channels that you want to collect data.
You can use the Enable All and Disable All buttons for quick configuration of manychannels.
2. Under Type, select the sensor type for each configured channel from the drop-down list
boxes. If all the channels are of the same type (thermocouple, RTD, or voltage), you can
use the Set all button to change all channels to the sensor type specified in the heading’s
drop-down list box.
3. Describe the channels, if desired, by entering text in the Label field corresponding to thechannel that you want to describe.
4. Click Save configuration to apply your changes. If you do not save before leaving thispage, your changes are lost.
You can also click the Discard changes button (before you save) to return to the previous
configuration, if desired.

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Chapter 5

Scan Rate
Use the Configuration -> Scan Rate web page to set the scan rate for all channels on the
instrument. A screen similar to the following appears:

To change your instrument’s scan rate, do the following:
1. Type a value, in Hertz, between the minimum and maximum shown in the Scan Rate
field.

Note: The scan rate that you specify is rounded to the closest "correct" value that the
instrument can accept without error. Internally, the 10 Hz clock is divided by an integer inthe range of 1 to 65535 (the internal clock divider) to determine the closest value. Whenyou save the scan rate configuration, the actual scan rate is shown.

2. Click Save configuration to apply your changes. If you do not save before leaving thispage, your changes are lost.
You can also click the Discard changes button (before you save) to return to the previous
configuration, if desired.

82

Configuring the Instrument Using the Web Interface

Filter Configuration
Use the Configuration -> Filter web page to configure the filter type used by the instrument.
A screen similar to the following appears:

You can choose one of the following filter types:• Raw – No filter. Provides fast response times, but the data may be difficult to interpret.
Use when you want to filter the data yourself.
The Raw filter type returns the data exactly as it comes out of the Delta-Sigma A/Dconverters. Note that Delta-Sigma converters provide substantial digital filtering above
the Nyquist frequency.
Generally, the only time it is desirable to use the Raw filter setting is if you are using fast
responding thermocouples, sampling them at higher speeds (> 1 Hz), and need as much
response speed as possible.
• Moving average – (The default filter setting.) Provides a compromise of filter
functionality and response time. This filter can be used in any application.
This low-pass filter takes the previous 16 samples, adds them together, and divides by 16.

83

Chapter 5

Alarm Limits Configuration
Use the Configuration -> Limits web page to define alarm conditions for specific enabledchannels that you want to measure. A screen similar to the following appears.

If the alarm condition occurs, the specified digital output line is turned on.
To set up limit checking, do the following:
1. Under Limit, click the Enable buttons next to the channels for which you want to define
limits. You can use the Disable All button to quickly stop limit checking on all channels.
For each channel:
2. Enter a value in the Low Limit text box.
3. Enter a value in the High Limit text box.
4. (Optional) Select a Digital Output line to set from the drop-down list box for this channel.
This line is set to 1 when the limit range (high or low) is exceeded.
When multiple channels are configured to set a digital output line, a logical OR condition
exists between them, and any value out of range sets the line to 1.
5. Click Save configuration to apply your changes. If you do not save before leaving thispage, your changes are lost.

84

Configuring the Instrument Using the Web Interface
You can also click the Discard changes button (before you save) to return to the previous
configuration, if desired.

Digital Input and Trigger Configuration
Use the Configuration -> Digital Input & Trigger web page to configure the digital input
lines of your instrument:

To change your digital input configuration, do the following:
1. Describe the digital input lines, if desired, by entering text in the Label fieldcorresponding to the digital input line that you want to describe.
2. To enable use of an external, digital trigger on digital input line 0, click the Enable
checkbox under the External trigger heading.
3. Click Save configuration to apply your changes. If you do not save before leaving thispage, your changes are lost.
You can also click the Discard changes button (before you save) to return to the previous
configuration, if desired.

85

Chapter 5

Digital Output Configuration
Use the Configuration -> Digital Out web page to configure the digital output lines of yourinstrument:

To change your digital output configuration, do the following:
1. Describe the digital output lines, if desired, by entering text in the Label fieldcorresponding to the digital output line that you want to describe.
2. Click Save configuration to apply your changes. If you do not save before leaving thispage, your changes are lost.
You can also click the Discard changes button (before you save) to return to the previous
configuration, if desired.

86

Configuring the Instrument Using the Web Interface

Measuring Data and Controlling the Instrument
If your browser supports Java, use the Control web pages start or stop data acquisition on thesensor channels or to update the value of the digital output line.

Starting and Stopping a Scan
Note: If your browser does not support Java, the Measurement & control -> Acquisition
page of the web interface is not supported. To acquire and view input data, use the
QuickDAQ application instead.

If your browser supports Java, start or stop a scan, using the Measurement & control ->Acquisition web page.

Press the Start scan button to begin acquiring data from the sensors. The measurements are
displayed on the screen. Press the Stop scan button to stop acquiring data from the sensors.
Notice the following aspects of the display:• When acquiring data, the Start scan button changes to say Stop scan and the currently
configured scan rate is displayed.

87

Chapter 5• Each box on the Meter tab represents one of the analog input channels, in the same
position as the physical connectors.
• If you configured custom labels for some of the channels, those labels are shown here
rather than the channel numbers.
• Red boxes indicate that the value is out of range for the specified sensor type.
• The values are updated only for the channels that you enabled, and at the scan rate you
configured.

Controlling the Digital Outputs
Use the Measurement & control -> Digital Output web page to view the current state of thedigital output lines, and manually change them if desired. A screen similar to the following
appears:

Green indicates that the digital output line/relay is closed; red indicates that the digital output
line/relay is open.

Note: You cannot change the configuration of digital output lines that were configured forlimit checking on the Configuration -> Limits page.

88

Configuring the Instrument Using the Web Interface
To change the status of a digital output line/relay, click the Open/Close toggle buttons under
the Change State heading for the digital output lines that you want to change. You can use
these controls to activate or deactivate an external device based on criteria other thantemperature that you define.

89

Chapter 5

Reading the Digital Inputs
Note: If your browser does not support Java, the Measurement & control -> Digital input
page of the web interface is not supported. To acquire and view input data, use the
QuickDAQ application instead.

If your browser supports Java, you can use the Measurement & control -> Digital Input web
page to view the current value of the digital input port while the instrument is scanning. A
screen similar to the following appears:

If you configured custom labels for the digital input lines, those labels are shown here.
The Current state LEDs show green if the digital input line is on (relay is closed) or red if thedigital input line is off (relay is open).

90Configuring the Instrument Using the Web Interface

Downloading Measurements
Note: This section applies only if your browser supports Java. If your browser does notsupport Java, downloading data to a file through the web interface is not supported.
If your browser supports Java, ensure that you have associated CSV files with Microsoft Excel
or Notepad, described on page 74, or the data will be displayed in the browser and not saved
to a file.

If your browser supports Java, you can use the File -> Download Measurements web page todownload your measurement results, including timestamp and limit values, if applicable, todisk. A screen similar to the following appears:

Measurements taken by the instrument are stored in a large circular buffer; when the buffer isfull, the oldest data is overwritten with the most recent data.
To download your data, do the following:
1. Click the Download button on this page.
If scanning has been stopped, all the data in the buffer is downloaded to acomma-separated CSV file, starting with the most recent data.

91

Chapter 5

Most Recent Data
Circular Buffer
Downloaded Data

Beginning of Buffer

End of Buffer

If scanning is in progress, a snapshot of the data from the most recent data (at the timethat the Download button was clicked) to the oldest data in the buffer is downloaded to acomma-separated CSV file.

Most Recent Data
Circular Buffer

Downloading Data

Oldest Data
Beginning of Buffer

End of Buffer

2. In the resulting dialog box, choose Open or Save.
 If you choose Open, the CSV file opens in the associated application (Microsoft Excel
or Notepad).
 If you choose Save, you can open the CSV file in Microsoft Excel, Notepad, or otherutilities for analysis at a later time.
Under some circumstances, your data may be displayed in a frame in the browser, or Excel
may open the data in the frame. Change your Microsoft Excel, Microsoft Explorer, andInternet Explorer settings to turn off these behaviors and open your files directly in Excel.

92

Part 2: Using Your
Instrument

6
Principles of Operation
Block Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Analog Input Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Digital I/O Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112

95

Chapter 6

Block Diagrams
This section includes the block diagrams for the DT8871U, DT8871, and DT8872 TEMPpoint
instruments, DT8873 VOLTpoint instrument, and DT8874 MEASURpoint instruments.

DT8871U Block Diagram
Figure 32 shows the block diagram of the DT8871U TEMPpoint instrument.

+
x20

24-BitA/D–
CJC Per
Point

64 kB
SRAM

1 of 8
Digital Input
Isolators

37-Pin D-Shell
Connector

Isolated
DC-DC

Isolation Barrier+10 nA Break
Detection

1 of 8
Digital Output
Isolators
Control
FPGA

RJ45

1 of up to 48 Channels
Ethernet
EmbeddedController

ENet
Link
LED
ENet
Activity
LED

Calibration
ROM

LAN
LED
Power LED
USB LED*
Limit LED
*The USB LED is not usedon this instrument.

Open TC LED
ID ROM

Figure 32: Block Diagram of the DT8871U TEMPpoint Instrument

96

Principles of Operation

DT8871 Block Diagram
Figure 33 shows the block diagram of the DT8871 instrument.

24-BitA/D

1 of 8
Digital Input
Isolators

37-Pin D-Shell
Connector

Isolated
DC-DC

64 kB
SRAM
Isolation Barrier+100 nA Break
Detection

1 of 8
Digital Output
Isolators
Control
FPGA

RJ45

CJC Per
Point
1 of up to 48 Channels
Ethernet

Calibration
ROM

EmbeddedController

ENet
Link
LED
ENet
Activity
LED
LAN
LED

*The USB LED is not usedon this instrument.

Power LED
USB LED*
Limit LED
Open TC LED*
ID ROM

Figure 33: Block Diagram of the DT8871 TEMPpoint Instrument

97Chapter 6

DT8872 Block Diagram
Figure 34 shows the block diagram of the DT8872 TEMPpoint instrument.

12+

2.5 Hz Filter
24-Bit
A/D

3
–
4

Sense

1 of 8
Digital Input
Isolators

37-Pin D-Shell
Connector

Isolated
DC-DC

64 kB
SRAM
Isolation Barrier+425 A
Current Source

1 of 8
Digital Output
Isolators
Control
FPGA

RJ45

Return1 of up to 48 Channels
Ethernet

Calibration
ROM

EmbeddedController

ENet
Link
LED
ENet
Activity
LED
LAN
LED

Power LED
USB LED**The USB and Open TC LEDs are notused on this instrument.

Limit LED
Open TC LED*
ID ROM

Figure 34: Block Diagram of the DT8872 TEMPpoint Instrument98Principles of Operation

DT8873 Block Diagram
Figure 35 shows the block diagram of the DT8873 VOLTpoint instrument.

–

Sense
Return24-BitA/D
60
10

1 of 8
Digital Input
Isolators

37-Pin D-Shell
Connector

1 M

2
3
4

2.5 Hz Filter

Isolation Barrier

1 +

64 kB
SRAM

IsolatedDC-DC

1 of 8
Digital Output
Isolators
Control
FPGA

RJ45

Gain Select1 of up to 48 Channels
Ethernet
Calibration
ROM

EmbeddedController

ENet
Link
LED
ENet
Activity
LED
LAN
LED

Power LED
USB LED**The USB and Open TC LEDs are
not used on this instrument.

Limit LED
Open TC LED*
ID ROM

Figure 35: Block Diagram of the DT8873 VOLTpoint Instrument99

Chapter 6

DT8874 Block Diagram
Figure 36 shows the block diagram of the DT8874 MEASURpoint instrument.

64 kB
SRAM

IsolatedDC-DC

1 of 8
Digital Output
Isolators+
24-BitA/D

x20

1 of 8
Digital Input
Isolators

37-Pin D-Shell
Connector+10 nA Break
Detection–
RJ45

CJC Per
Point
Channels 0 to 15
Ethernet
Isolated
DC-DC

1
2

+

2.5 Hz Filter
24-BitA/D

3–
4

Isolation Barrier+425 A
Current Source

Control
FPGA

Sense

ENet
Link
LED
ENet
Activity
LED

EmbeddedController

LAN
LED
Power LED

ReturnChannels 16-31

USB LED*
Limit LED

1 +

1 M

2
3
–
4

Isolated
DC-DC

2.5 Hz Filter

Sense
ReturnOpen TC LED*

24-BitA/D

ID ROM

60
10
Gain SelectChannels 32-47

Calibration
ROM*The USB LED is not
used on this
instrument.

Figure 36: Block Diagram of the DT8874 MEASURpoint Instrument100Principles of Operation

Analog Input Features
This section describes the following features of the analog input (A/D) subsystem on
TEMPpoint, VOLTpoint, and MEASURpoint instruments:• Analog input channels, described on this page
• Input ranges, described on page 104• Resolution, described on page 106• Calibration, described on page 106• Sample clock, described on page 107• Trigger source, described on page 107• Conversion modes, described on page 108• Filtering, described on page 110• Data format, described on page 110• Error conditions, described on page 111

Analog Input Channels
TEMPpoint, VOLTpoint, and MEASURpoint instruments provide up to 48 analog input
channels. The number of channels and the channel types supported (thermocouple, RTD, orvoltage input) depend on the specific instrument model you purchased, as shown in Table 3.

Table 3: Number and Type of Analog Input Channels
Instrument
Type
TEMPpoint

Models# of Analog Input
Channels

Channel Types

DT8871U-8 and DT8871-8

8

8 thermocouple inputs (numbered 0 to 7)

DT8871U-16 and DT8871-16

16

16 thermocouple inputs (numbered 0 to 15)

DT8871U-24 and DT8871-24

24

24 thermocouple inputs (numbered 0 to 23)

DT8871U-32 and DT8871-32

32

32 thermocouple inputs (numbered 0 to 31)

DT8871U-40 and DT8871-40

40

40 thermocouple inputs (numbered 0 to 39)

DT8871U-48 and DT8871-48

48

48 thermocouple inputs (numbered 0 to 47)

DT8872-8

8

8 RTD inputs (numbered 0 to 7)

DT8872-16

16

16 RTD inputs (numbered 0 to 15)

DT8872-24

24

24 RTD inputs (numbered 0 to 23)

DT8872-32

32

32 RTD inputs (numbered 0 to 31)

DT8872-40

40

40 RTD inputs (numbered 0 to 39)

DT8872-48

48

48 RTD inputs (numbered 0 to 47)

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Table 3: Number and Type of Analog Input Channels (cont.)
Instrument
Type
VOLTpoint

MEASURpoint

Models# of Analog Input
Channels

Channel Types

DT8873-8

8

8 voltage inputs (numbered 0 to 7)

DT8873-16

16

16 voltage inputs (numbered 0 to 15)

DT8873-24

24

24 voltage inputs (numbered 0 to 23)

DT8873-32

32

32 voltage inputs (numbered 0 to 31)

DT8873-4040

40 voltage inputs (numbered 0 to 39)

DT8873-48

48

48 voltage inputs (numbered 0 to 47)

DT8874-16T-16R-16V

48

16 thermocouple inputs (numbered 0 to 15)
16 RTD inputs (numbered 16 to 31)
16 voltage inputs (numbered 32 to 47)

Thermocouple Input Channels
For channels that support thermocouples, you can attach a voltage input or any of thefollowing thermocouple types in a mix and match fashion: B, E, J, K, N, R, S, and/or T.
By default, these channels are configured for voltage inputs. You can specify the thermocouple
types for channels over the LAN using the web interface, as described in “Channel
Configuration” on page 80, in the QuickDAQ application, or by using an API call in yourapplication program. You can also use standard SCPI commands over VISA or sockets, if
desired.

Note: In a mix-and-match system, it is easy to accidentally mismatch the software andhardware configuration for a channel. Therefore, it is recommended that you pay particularattention when configuring channels, since the resultant errors may be not large enough to
notice initially, but may be significantly larger than the accuracy specification for the
instrument.

Since each channel has its own 24-bit A/D, analog inputs are measured simultaneously. Referto page 108 for more information on specifying the channels for a scan.
Table 4 lists the supported measurement range for each thermocouple type. (Refer to page 104
for information on the supported input range for voltage measurements.)

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Principles of Operation

Table 4: Supported Measurement Range for Each Thermocouple Type
Supported Measurement Range
Thermocouple
Type

Minimum

MaximumB250 C (482 F)

1820° C (3308° F)

E–200 C (–328 F)

1000° C (1832° F)

J–210 C (–346 F)

1200C (2192° F)

K–200 C (–328 F)

1372° C (2502° F)

N–200 C (–328 F)

1300° C (2372° F)

R–50 C (–58 F)

1768° C (3214° F)

S–50 C (–58 F)

1768° C (3214° F)

T–200 C (–328 F)

400° C (752° F)

Refer to Appendix A for the thermocouple accuracy of thermocouple channels over the
dynamic range of the instrument.
Cold Junction Compensation
Each thermocouple channel has its own cold-junction compensation (CJC) at the input. The
software reads the value of the CJC input along with the value of the analog input channel andautomatically corrects for errors based on the specified thermocouple type and thethermocouple linearization data stored in onboard ROM.
A separate multiplexed A/D is used to acquire all the CJC input values. The software takes
care of correlating the CJC measurements with the analog input measurements.

Note: The software provides the option of returning CJC values in the data stream. This
option is seldom used, but is provided if you want to implement your own temperature
conversion algorithms in software when using continuous operations. Refer to page 110 for
more information on this feature.

Open Thermocouple Detection
Break detection circuitry (+10 nA on the DT8871U and DT8874; +100 nA on the DT8871) isprovided for thermocouple channels to ensure that open thermocouples are detected. The
Open (OPN) LED on the rear panel lights when this condition occurs; see Figure 14 on page 42
for the location of this LED.

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Chapter 6
In addition, the software returns the value SENSOR_IS_OPEN (99999 decimal) for any
channel that was configured for a thermocouple input and has either an open thermocouple
or no thermocouple connected to it. This value is returned anytime a voltage greater than 100
mV is measure on the input, since this value is greater than any legitimate thermocouple
voltage.
If the channel is configured for a voltage input (not a thermocouple type), the Open (OPN)
LED never lights and the SENSOR_IS_OPEN value is not returned. Instead, the voltage value
is returned. If no input is connected to the channel, the software returns a value ofapproximately 0.7 V due to the open thermocouple detection pull-up circuit.

RTD Channels
For channels that support RTDs, you can attach a voltage input or any of the following RTD
types in a mix and match fashion: Platinum 100  (Pt100), Platinum 500  (Pt500), or Platinum
1000  (Pt1000) RTD using an European alpha curve of 0.00385 or an American alpha curve of
0.00392. The supported temperature measurement range for these RTD types is –200 C(–328 F) to 850 C (1562 F). You can also measure a resistance value between 0 and 4k Ohms,
if desired. (Refer to page 104 for information on the supported input range for voltage
measurements.)
By default, all channels are configured for voltage inputs. You can specify the RTD types forchannels over the LAN using the web interface, as described in “Channel Configuration” onpage 80, in the QuickDAQ application, or by using an API call in your application program.
You can also use standard SCPI commands over VISA, if desired.

Note: In a mix-and-match system, it is easy to accidentally mismatch the software andhardware configuration for a channel. Therefore, it is recommended that you pay particularattention when configuring channels, since the resultant errors may be not large enough to
notice initially, but may be significantly larger than the accuracy specification for the
instrument.

Since each channel has its own 24-bit A/D, analog inputs are measured simultaneously. Referto page 108 for more information on specifying the channels for a scan.

Input Ranges
The input voltage range that is supported by your TEMPpoint, VOLTpoint, or MEASURpoint
instrument depends on the specific instrument model that you purchased, as shown in
Table 5.

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Principles of Operation

Table 5: Supported Input Ranges
Instrument
Type
TEMPpoint

Models

Input Range

DT8871U±0.75 V for all channels

DT8871±1.25 V for all channels

DT8872±1.25 V for all channels

VOLTpoint

DT8873±10 V or ±60 V(software-selectable for each channel)aMEASURpoint

DT8874-16T-16R-16V±0.75 V for channels 0 to 15;±1.25 V for channels 15 to 31;±10 V or ±60 V for channels 32 to 47(software-selectable for each channel)aa. Note that the maximum input voltage for the ±60 V range cannot be more than 30 Vrms, 42.4 Vpk,
60 VDC.

Out of Range Data for Thermocouple Channels
Each thermocouple type corresponds to an allowable voltage range. If a voltage is measured
on the input that is outside of the legal range for the selected thermocouple type, the channel
may be configured for the wrong type of thermocouple or something other than athermocouple may be connected to the channel.
For channels configured with a thermocouple type of None (voltage), the Limit (LMT) LED on
the rear panel of the instrument lights to alert you when the voltage is out of range; see Figure
14 on page 42 for the location of this LED.
For channels configured with a thermocouple type other than None (voltage), the LMT LED
lights when the temperature limit is out of range for the specified thermocouple type.
In addition, if the input voltage is less than the legal voltage range for the selected
thermocouple type, the software returns the value TEMP_OUT_OF_RANGE_LOW (–88888
decimal). If the input voltage is greater than the legal voltage range for the selected
thermocouple type, the software returns the value TEMP_OUT_OF_RANGE_HIGH (88888
decimal).

Note: If you are continuously measuring from a properly configured thermocouple input
channel and the thermocouple opens or becomes disconnected, the open thermocouple
pull-up circuit causes the input voltage to rise to approximately 0.7 V over a few seconds.
In this case, the temperature value rises very quickly, and you will receive the
TEMP_OUT_OF_RANGE_HIGH (88888 decimal) value followed by the OPEN_SENSOR(99999 decimal) value. In this case, the OPN LED lights when the open thermocouple isdetected and the LMT LED lights when the temperature limit is out of range for thethermocouple type.

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Chapter 6

Out of Range Data for RTD Channels
Each RTD type corresponds to an allowable voltage range. If a voltage is measured on the
input that is outside of the legal range for the selected RTD type, the channel may be
configured for the wrong type of RTD or something other than an RTD may be connected tothe channel.
For channels configured with a RTD type of voltage, the Limit (LMT) LED on the rear panel ofthe instrument lights to alert you when the voltage is out of range (greater than +1.25 V or lessthan –1.25 V); see page 42 for the location of this LED. For channels configured with an RTD
type other than voltage, the LMT LED lights when the temperature limit is out of range for the
specified RTD type.
In addition, if the input voltage is less than the legal voltage range for the selected RTD type,the software returns the value TEMP_OUT_OF_RANGE_LOW (–88888.0 decimal). If the
input voltage is greater than the legal voltage range for the selected RTD type, the software
returns the value TEMP_OUT_OF_RANGE_HIGH (88888.0 decimal).

Out of Range Data for Voltage Channels
Each voltage input channel has an allowable voltage range (±10 V or ±60 V on MEASURpoint
instruments). You configure the input range for each channel using software. If a voltage ismeasured on the input that is outside of the legal range for that channel, the Limit (LMT) LED
on the rear panel of the instrument lights to alert you; see page 42 for the location of this LED.

Resolution
TEMPpoint, VOLTpoint, and MEASURpoint instruments support a resolution of 24 bits forthe analog input subsystem; you cannot specify the resolution in software.

Calibration
Each TEMPpoint, VOLTpoint, and MEASURpoint instrument is factory-calibrated to meet or
exceed its published specifications using standards traceable to NIST.
The calibration process includes multiple steps. First, the A/D on each channel is calibrated
for offset and gain; these values (including the zero point) are stored in ROM. Then, each CJC
circuit is calibrated for thermocouple input channels, and the reference current ischaracterized for RTD channels.
While each instrument was designed to preserve high accuracy measurements over time, it isrecommended that your instrument be recalibrated every year to ensure that it meets orexceeds specifications.
You can calibrate your instrument in the field using precise calibration equipment and the
Measurement Instrument Calibration Utility. Refer to the help file for the Measurement
Instrument Calibration Utility for detailed information.

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Principles of Operation
Optionally, you can return your instrument to Data Translation for recalibration. For
information on factory recalibration, contact Data Translation at 508-946-5100 (if you are in theUSA) or call your local distributor (if you are located outside the USA); see our web site(www.mccdaq.com) for the name and telephone number of your nearest distributor.
In addition, each instrument auto-calibrates on each power-up cycle to guarantee
high-accuracy measurements. This process, also known as auto-zeroing, resets the zero pointof each A/D. You can also auto-calibrate the instrument at any time (as long as acquisition is
not in progress) using a software command. Refer to your software documentation for more
information on the auto-calibration feature.

Sample Clock Source
TEMPpoint, VOLTpoint, and MEASURpoint instruments support an internal clock with amaximum sampling rate of 10 Samples/s.
Use software to specify an internal clock source and a clock frequency between
0.000152590219 Hz and 10.0 Hz.

Note: The clock frequency that you specify is rounded to the closest "correct" value that the
instrument can accept without error. Internally, the 10 Hz clock is divided by an integer in therange of 1 to 65535 (the internal clock divider) to determine the closest value. Using software,
you can query this setting to determine the actual clock frequency that is used.

When the continuous operation is started, all the channels specified in the channel list are read
simultaneously at the specified clock frequency.

Trigger Source
A trigger is an event that occurs based on a specified set of conditions. Acquisition starts when
the instrument detects the initial trigger event and stops when you stop the operation.
TEMPpoint, VOLTpoint, and MEASURpoint instruments support the following trigger
sources for starting analog input operations:• Software trigger – A software trigger event occurs when you start the analog input
operation (the computer issues a write to the instrument to begin conversions).
• External digital trigger – An external digital trigger event occurs when the instrument
detects a voltage from +3 V to +28 V DC on digital input line 0. Initially, the external signal
must be low and then go high for at least 100 ms to be detected as a trigger. Once
triggered, the state of digital input 0 is ignored.

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Chapter 6

Conversion Modes
TEMPpoint, VOLTpoint, and MEASURpoint instruments support simultaneous single value
and continuous scan conversion modes for reading input measurements.
This section describes each of these conversion modes.

Simultaneous Single-Value Operations
If you want a snapshot of all the analog input channels at one point in time, you can perform asimultaneous single-value operation, also called a single values operation, using SCPI
commands.

Note: This operation mode is supported in SCPI only; it is not supported by the IVI-COM
driver or the instrument’s web interface.

Use one of the :MEASure SCPI commands to specify the channels that you want to sample
and the configuration of the channels, if needed. One single value is then acquired from eachanalog input channel simultaneously and returned.
If you need to continuously acquire data from one or more channels use continuous scanmode, described next, instead.

Continuous Scan Mode
Continuous scan mode takes full advantage of the capabilities of the TEMPpoint, VOLTpoint,
and MEASURpoint instruments. Use continuous scan mode if you want to accurately control
the period between successive simultaneous conversions of specific channels.
In addition to the analog input channels, this conversion mode allows you to read the digital
input port (all 8 digital input lines) as part of the analog input data stream. This feature isparticularly useful when you want to correlate the timing of analog and digital events.
Specifying Analog Input Channels
Using software, enable the analog input channels that you want to sample by specifying thechannel numbers in the channel list. You can also read the value of the digital input port
through the analog input data stream by specifying the digital input channel in the channel
list; the number of the digital input channel depends on how many channels the TEMPpoint,
VOLTpoint, or MEASURpoint instrument provides, as shown in Table 6.

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Principles of Operation

Table 6: Supported Channels for Continuous Operations
Total Number of
Analog Input Channels

Channel for Reading
the Digital Input Port

0 to 7

8

0 to 15

16

0 to 23

24

0 to 31

32

0 to 3940

0 to 47

48

The channels are read in order from the lowest channel number to the highest channel numberin the list of enabled channels; this process is known as a scan.
How Continuous Scan Works
When you issue a command to start the scan, the instrument simultaneously samples all theanalog input channels, CJC inputs (if applicable), and the digital input port, and converts theanalog inputs to temperature, resistance, or voltage based on the sensor type. If the channel isenabled, the sampled data is placed in the FIFO on the instrument.
The FIFO on the instrument is used as a circular buffer. Acquisition continues indefinitely
until you stop the operation. When the FIFO is full, the operation wraps to the beginning of
the FIFO; values are overwritten starting at the first location in the FIFO. It is up to yourapplication to retrieve the data from the FIFO; refer to your software documentation for more
information.
The conversion rate is determined by the frequency of the input sample clock; refer to page107 for more information about the input sample clock. The sample rate, which is the rate at
which a single entry in the channel list is sampled, is the same as the conversion rate due tothe simultaneous nature of the MEASURpoint instrument.
Figure 37 illustrates scanning a list of three enabled channels: channel 0, channel 1, andchannel 2. In this example, analog input data is acquired simultaneously on each clock pulseof the input sample clock. Data is acquired continuously.

Chan 2Chan 2Chan 2Chan 2Chan 1Chan 1Chan 1Chan 1Chan 0Chan 0Chan 0Chan 0Input
SampleClockData is acquired continuously
Operation starts

Figure 37: Continuous Scan Mode

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Chapter 6

Filtering
TEMPpoint, VOLTpoint, and MEASURpoint instruments use a Delta-Sigma analog-to-digitalconverter (ADC) for each analog input channel to provide simultaneous sampling of all
inputs. The Delta-Sigma converter operates at 10 Hz effectively providing a filter that rejects
50 Hz and 60 Hz power line frequency components and that removes aliasing, a condition
where high frequency input components erroneously appear as lower frequencies after
sampling.
In addition to the filter provided in hardware, you can further reduce noise by selecting one of
the following filter options in software: Moving Average or Raw. Refer to page 83 and to yoursoftware documentation for more information on selecting a filter type.

Data Format
TEMPpoint, VOLTpoint, and MEASURpoint instruments return data as 32-bit floating-pointvalues. How the data is returned depends on the channel type, as described in the following
subsections.

Data Format for Thermocouple Channels
If you specify a thermocouple type of None for a thermocouple input channel, a voltage
measurement is selected and the instrument returns a voltage value. For the DT8871U andDT8874 instruments, the value is in the range of ±0.075 V; for the DT8872 instrument, thevalue is in the range of ±1.25 V. For all other thermocouple types, a temperature value, indegrees C, or one of the error constants, described on page 111, is returned.
In normal operation, one floating-point value is returned for each enabled channel (including
the digital input port). If you enable the capability of returning CJC data in the data stream,
described on page 103, two floating-point values are returned in the data stream for eachenabled analog input channel. The first value in the pair represents the temperature (orvoltage) of the channel; the second value in the pair represents the CJC temperature (indegrees C) for that channel.

Data Format for RTD Channels
If you specify an RTD type of None for an RTD input channel, a voltage measurement isselected and the instrument returns a voltage value in the range of ±1.25 V. If you specify an
RTD type of Ohms, a resistance value is returned. For all other RTD types, a temperature
value, in degrees C, or one of the error constants, described on page 111, is returned.
One floating-point value is returned for each enabled channel (including the digital inputport).

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Principles of Operation

Data Format for Voltage Channels
For voltage channels on a MEASURpoint instrument, a voltage value in the range of ±10 V or
±60 V is returned, depending on how the channel was configured. Note that the maximum
input voltage for the ±60 V range cannot be more than 30 Vrms, 42.4 Vpk, 60 VDC.
One floating-point value is returned for each enabled channel (including the digital inputport).

Error Conditions
TEMPpoint, VOLTpoint, and MEASURpoint instruments report overrun errors by sending anoverrun event to the application program. If this error condition occurs, the instrument stops
acquiring and transferring data to the host computer. To avoid this error, try one or more of
the following:• Reduce the sample rate
• Close any other applications that are running• Run the program on a faster computer
Additionally, the following constants may be reported to the host:• 99999.0 – SENSOR_IS_OPEN, described on page 103• 88888.0 – TEMP_OUT_OF_RANGE_HIGH, described on page 105 and page 106• –88888.0 – TEMP_OUT_OF_RANGE_LOW, described on page 105 and page 106
If any of these constants is reported, the A/D subsystem continues to acquire data; the error
condition is cleared when the data falls within range.

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Chapter 6

Digital I/O Features
TEMPpoint, VOLTpoint, and MEASURpoint instruments provide 8 digital input lines and 8
digital output lines that you can use to control external equipment, including solid-state ormechanical relays.
This section describes the following digital I/O features:• Digital input lines, described below• Digital output lines, described on page 113• Channel-to-channel functional isolation, described on page 113• Resolution, described on page 113• Operation modes, described on page 113

Digital Input Lines
TEMPpoint, VOLTpoint, and MEASURpoint instruments feature eight, isolated, digital input
lines.
Digital inputs operate from +3 to +28 V DC, with a switching time of 2 ms maximum. Figure
38 shows the digital input circuitry; a 2.2 k resistor is used in series with the LED in the
opto-isolator input.

2.2K+
Digital Input
1 of 8 Opto-Isolators
Figure 38: Digital Input Circuitry

A digital line is high (switch is closed) if its value is 1; a digital line is low (switch is open) if its
value is 0.

112

Principles of Operation

Digital Output Lines
TEMPpoint, VOLTpoint, and MEASURpoint instruments feature eight, latched and isolated
digital output lines. The outputs are solid-state relays that operate at ±30 V and 400 mA peak(AC or DC). Switching time is 2 ms maximum.
Figure 39 shows the digital output circuitry.

1 of 8 Solid State Relays
Figure 39: Digital Output Circuitry

Digital outputs resemble a switch; the switch is closed if the state of the digital output line is 1,
and the switch is open if the state of the digital output line is 0. On power up or reset, thedigital outputs are disabled.

Channel-to-Channel Functional Isolation
Each TEMPpoint, VOLTpoint, and MEASURpoint instrument includes channel-to-channel
functional isolation of up to 60 V between digital I/O lines.

Resolution
Each TEMPpoint, VOLTpoint, and MEASURpoint instrument provides 8 bits of resolution forthe digital input port to accommodate the 8 digital input lines and 8 bits of resolution for thedigital output port to accommodate the 8 digital output lines. These lines are organized as
isolated, dedicated ports. You cannot configure port resolution through software.

Operation Modes
Using software, you can read from a single digital input line or the entire digital input port, or
write to a single digital output line or the entire digital output port. You can also return thevalue of the entire digital input port in the analog input data stream if you want to correlateanalog input data with digital events; refer to page 108 for more information.

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Chapter 6

114

7
Troubleshooting
General Checklist . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
If Your Instrument Needs Factory Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119

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Chapter 7

General Checklist
Should you experience problems using a TEMPpoint, VOLTpoint, or MEASURpoint
instrument, do the following:
1. Read all the documentation provided for your product, including any “Read This First”
information.
2. Install the latest software from the web athttps://www.mccdaq.com/downloads/DTSoftware/MEASURpoint.
3. Check that your system meets the requirements stated in Chapter 2.
4. Check that you have installed your hardware properly using the instructions in Chapter 3.
5. Check that you have wired your signals properly using the instructions in Chapter 4.
6. Search the DT Knowledgebase in the Support section of the Data Translation web site (atwww.mccdaq.com) for an answer to your problem.
If you still experience problems, try using the information in Table 7 to isolate and solve theproblem. If you cannot identify the problem, refer to page 118.

Table 7: Troubleshooting Problems
Symptom

Possible Cause

Instrument is
not found.

The instrument cannot
communicate with the
network.

Possible Solution
Ensure that your instrument is properly connected; see theinstructions in Chapter 3.
If your PC has a static IP address, reconfigure it for Auto-IP using
the instructions on page 145.
Check your LAN configuration; see the instructions on page 79.
Check the IP address of the instrument by opening a Command
Prompt window (Start -> Programs -> Accessories -> Command
Prompt) and entering the command"ipconfig /all". The IP settings of your instrument are returned.
Ping the instrument by opening a Command Prompt window(Start -> Programs -> Accessories -> Command Prompt) andentering the command "ping address", where address is the IP
address of your instrument. If a timeout message is returned, theIP address is incorrect. If a "no host" error message is returned,
the subnet mask is incorrect. Refer to page 41 for more
information on IP and subnet addresses.
If needed, reset the instrument using the instructions on page 44.

116Troubleshooting
Table 7: Troubleshooting Problems (cont.)
Symptom
Instrument
does notrespond.

Possible Cause

Possible Solution

The instrument configuration
is incorrect.

Check your LAN configuration; see the instructions on page 79.
Check the IP address of the instrument by opening a Command
Prompt window (Start -> Programs -> Accessories -> Command
Prompt) and entering the command "ipconfig /all". The IP settingsof your instrument are returned.
Ping the instrument by opening a Command Prompt window(Start -> Programs -> Accessories -> Command Prompt) andentering the command "ping address", where address is the IP
address of your instrument. If a timeout message is returned, theIP address is incorrect. If a "no host" error message is returned,
the subnet mask is incorrect. Refer to page 41 for more
information on IP and subnet addresses.
If needed, reset the instrument using the instructions on page 44.

Intermittent
operation.

Data appears
to be invalid.

The instrument is damaged.

Contact Data Translation for technical support; refer to page 118.

Loose connections orvibrations exist.

Check your wiring and tighten any loose connections or cushion
vibration sources; see the instructions in Chapter 4.

The instrument is overheating.

Check environmental and ambient temperature; consult the
specifications on page 136 of this manual and the documentation
provided by your computer manufacturer for more information.

Electrical noise exists.

Check your wiring and either provide better shielding or rerouteunshielded wiring; see the instructions in Chapter 4.

An open connection exists.

Check your wiring and fix any open connections; see theinstructions in Chapter 4.

A transducer is not connectedto the channel being read.

Check the transducer connections; see the instructions in
Chapter 4.

The thermocouple, RTD, orvoltage input that youconnected to the channel
does not match the software
configuration for that channel.

Check your wiring and ensure that what you specify in software
matches your hardware configuration; see the instructions in
Chapter 4.

Your instrument may needrecalibration.

The instrument is calibrated at the factory. Thereafter, yearlycalibration is recommended. Use the Measurement Instrument
Calibration Utility, described on page 21, or return your instrument
to Data Translation for recalibration.
For information on factory recalibration, contact Data Translation
at 508-946-5100 (if you are in the USA) of call your local
distributor (if you are located outside the USA); see our web site(www.mccdaq.com) for the name and telephone number of yournearest distributor.

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Chapter 7

Technical Support
Note: TEMPpoint, VOLTpoint, and MEASURpoint instruments have a 1 year warranty fromthe factory. If you open the instrument’s enclosure, you will void this warranty.

If you have difficulty using your TEMPpoint, VOLTpoint, or MEASURpoint instrument, Data
Translation’s Technical Support Department is available to provide technical assistance.
To request technical support, go to our web site at http://www.mccdaq.com and click on the
Support link.
When requesting technical support, be prepared to provide the following information:• Your product serial number• The hardware/software product you need help on• The version of the MEASURpoint Software that you are using• Your contract number, if applicable
If you are located outside the USA, contact your local distributor; see our web site(www.mccdaq.com) for the name and telephone number of your nearest distributor.

118Troubleshooting

If Your Instrument Needs Factory Service
Most hardware models can be functionally tested, evaluated for repairs (if needed), andcalibrated to factory specifications. An RMA # must be obtained from Application
Engineering in advance of sending any product back to Measurement Computing. Customers
outside of the USA must contact their local distributor for a return procedure. Calibration
certificates for most analog models can be obtained for a fee (certificate must be requested attime of RMA # assignment).

119Chapter 7120

ASpecifications
Basic Instrument Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Thermocouple Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
RTD Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Temperature Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Voltage Measurement Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Isolation and Protection Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Memory Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Digital I/O Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Power, Physical, and Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Regulatory Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Connector Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
External Power Supply Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141

Note: All analog input specifications are based on the Moving Average filter type.

121

Appendix A

Basic Instrument Specifications
Table 8 lists the basic instrument specifications for the DT8871, DT8871U, DT8872, DT8873,
and DT8874 instruments. For basic environmental specifications, please see page 136.

Table 8: Basic Instrument Specifications

122

FeatureSpecifications

Number of channels in channel list

Up to 48 analog input channels and one digital input port

A/D converter typeHigh stability 24-bit Sigma-Delta

Measurement category ratings

Do not connect to signals or use for measurements within
measurement categories II, III, or IV

Specifications

Thermocouple Specifications
Table 9 lists the specifications for thermocouple channels on the DT8871, DT8871U, andDT8874 instruments.

Table 9: Thermocouple Specifications
FeatureSpecifications

Thermocouple types (software-selectable)

B, E, J, K, N, R, S, T

A/D resolution

24-bits

Sample rate

10 Samples/s

Thermal disturbance channel-to-channel

None

Upscale break detection current
DT8871U and DT8874:
DT8871:+10 nA+100 nA

System temperature error
DT8871U and DT8874:
DT8871:

See Table 10 and Table 11 on page 124
See Table 12 on page 126

123

Appendix A

System Temperature Error for the DT8871U and DT8874
Table 10 lists the typical accuracy of the DT8871U and DT8874 for each thermocouple type atseveral temperature points over the dynamic range of the instrument.
Table 10: Typical Thermocouple Accuracy of the DT8871U and DT8874
Thermocouple Typea
Input
Temp.

J

K

T

E

S

R

B

N

–100C

0.17C

0.17C

0.16C

0.16C---------------------------------

0.16C

0C

0.15C

0.16C

0.16C

0.15C

0.20C

0.20C-----------

0.16C

100C0.18C

0.15C

0.16C

0.15C

0.18C

0.18C-----------

0.15C

300C0.15C

0.17C

0.16C

0.15C

0.18C

0.18C

0.23C

0.15C

500C0.15C

0.15C-----------

0.15C

0.18C

0.17C

0.21C

0.15C

700C0.15C

0.15C-----------

0.16C

0.18C

0.18C

0.17C

0.16C

900C0.15C

0.17C-----------

0.17C

0.18C

0.18C

0.19C

0.16C

1100C

0.15C

0.16C----------------------

0.19C

0.18C

0.18C

0.16C

1400C--------------------------------------------

0.18C

0.18C

0.17C-----------

a. Conditions for accuracy measurements:
MEASURpoint warm-up time of 1 hour. Inclusive of typical 0.15C CJC error. Exclusive of thermocouple
errors.

Table 11 lists the maximum accuracy of the DT8871U and DT8874 for each thermocouple typeat several temperature points over the dynamic range of the instrument.
Table 11: Maximum Thermocouple Accuracy of the DT8871U and DT8874
Thermocouple Typea
Input
Temp.

J

K

T

E

S

R

B

N

–100C

0.35C

0.38C

0.39C

0.34C---------------------------------

0.43C

0C

0.33C

0.35C

0.35C

0.32C

0.96C

0.98C-----------

0.40C

100C0.34C

0.31C

0.34C

0.31C

0.77C

0.76C-----------

0.37C

300C0.31C

0.36C

0.32C

0.30C

0.67C

0.65C1.52C

0.35C

500C0.30C

0.33C-----------

0.30C

0.64C

0.61C1.02C

0.34C

700C0.30C

0.33C-----------

0.31C

0.62C

0.58C

0.80C

0.35C

900C0.30C

0.36C-----------

0.31C

0.60C

0.56C

0.72C

0.35C

1100C

0.31C

0.35C----------------------

0.59C

0.54C

0.65C

0.35C

1400C--------------------------------------------

0.57C

0.53C

0.59C-----------

a. Conditions for accuracy measurements:
MEASURpoint warm-up time of 1 hour. Maximum accuracy inclusive of 0.25C CJC error. Exclusive of
thermocouple errors.

124Specifications
The histograms shown in Figure 40 and Figure 41 characterize the Gaussian system noise
distribution for each of the available filter types on the DT8871U and DT8874. Note thatconverting V error to temperature error depends on thermocouple type. For example, a K
thermocouple changes approximately 39 V per degrees C; therefore, a noise level of 0.1 V
adds less than 0.003 C error (0.1 V / 39 V) for a type K thermocouple.

Figure 40: System Noise on the DT8871U and DT8874 Using No Software Filter (Raw Filter)

Figure 41: System Noise on the DT8871U and DT8874 Using the Moving Average Filter

125Appendix A

System Temperature Error for the DT8871
Table 12 lists the typical accuracy of the DT8871 for each thermocouple type at several
temperature points over the dynamic range of the instrument.

Table 12: Typical Thermocouple Accuracy of the DT8871
Thermocouple Typea
Input
Temperature

J

K

T

E

S

R

B

N

–100C

0.33C

0.37C

0.38C

0.31C---------------------------------

0.44C

0C

0.30C

0.33C

0.33C

0.28C

1.12C

1.14C-----------

0.39C

100C0.31C

0.29C

0.31C

0.27C

0.88C

0.86C-----------

0.35C

300C0.29C

0.34C

0.29C

0.26C

0.75C

0.71C

1.84C

0.33C

500C0.28C

0.31C-----------

0.26C

0.71C

0.66C

1.20C

0.33C

700C0.27C

0.30C-----------

0.27C

0.68C

0.63C

0.92C

0.33C

900C0.27C

0.34C-----------

0.28C

0.66C

0.60C

0.80C

0.33C

1100C

0.28C

0.34C----------------------

0.64C

0.58C

0.71C

0.34C

1400C--------------------------------------------

0.62C

0.56C

0.64C-----------

a. Conditions for accuracy measurements:
MEASURpoint warm-up time of 1 hour. Inclusive of typical 0.2C CJC error (maximum CJC error is 0.3C).
Exclusive of thermocouple errors.

The histograms shown in Figure 42 and Figure 43 characterize the Gaussian system noise
distribution for each of the available filter types on the DT8871. Note that converting V error
to temperature error depends on thermocouple type. For example, a K thermocouple changes
approximately 39 V per degrees C; therefore, a noise level of 10 V adds 0.3 C error(10 V / 39 V) for a type K thermocouple.

126

Specifications

Figure 42: System Noise on the DT8871 Using No Software Filter (Raw Filter)

Figure 43: System Noise on the DT8871 Using the Moving Average Filter

127Appendix A

RTD Specifications
Table 13 lists the specifications for RTD channels on the DT8872 and DT8874 instruments.

Table 13: RTD Specifications
FeatureSpecifications

RTD types (software-selectable)

Platinum 100 , 500 , and 1000 

A/D converter resolution

24-bits

Sample rate

10 Samples/s

Supported temperature range–200 to +850C (European standard)

Current source
Absolute current:

425 A, ±0.5% at 25 C (calibrated in firmware)

Drift:

10 ppm/C maximum

Drift per year:±100 ppm typicalInternal reference+1.250 ±0.002 V

Thermal disturbance channel-to-channel

None

Supported RTD alpha curves

See Table 14

Table 14 lists the RTD alpha curves that are supported by RTD channels.

Table 14: Supported RTD Alpha Curves
Alpha (Average
Temperature
Coefficient ofResistance (/C))
0.00385

0.00392

128

NominalResistance at
0C
100

98.129 

Organization

Standard

British Standard

BS1904: 1984

Deutschen Institut
fur Normung

DIN 43760: 1980

Scientific Appartus
Manufacturers ofAmerica

SAMA
RC-4-1966

Specifications

Temperature Specifications
Table 15 lists the temperature specifications for thermocouple channels on the DT8871,
DT8871U, and DT8874 instruments.

Table 15: Temperature Stability Specifications for Thermocouple Channels
FeatureSpecifications

Additional error due to ambient temperaturechangeaJ-type thermocouple:
K-type thermocouple:
B-type thermocouple:
E-type thermocouple:
N-type thermocouple:
R-type thermocouple:
S-type thermocouple:
T-type thermocouple:

0.010C per degree ambient change, typical
0.011C per degree ambient change, typical
0.014C per degree ambient change, typical
0.010C per degree ambient change, typical
0.011C per degree ambient change, typical
0.012C per degree ambient change, typical
0.012C per degree ambient change, typical
0.010C per degree ambient change, typical

MEASURpoint warm-up time

1 hourCJC
Error (maximum):±0.25C

Accuracy:

Corrected in ROM @ 25 C to zero error

Drift per year:±50 ppm typicala. Includes the A/D reference, gain, and CJC errors.

129

Appendix A
Table 16 lists the temperature specifications for RTD channels on the DT8872 and DT8874
instruments.
Table 16: Temperature Specifications for RTD Channels
FeatureSystem temperature errora
Pt100:

Specifications

Offset (typical): ±0.03° C
Offset (maximum): ±0.30° C
RMS noise: 0.03° C
Temperature resolution: 0.002° C
Maximum system error: ±0.80° Cb

Pt500:

Offset (typical): ±0.007° C
Offset (maximum): ±0.07° C
RMS noise: 0.007° C
Temperature resolution: 0.0004° C
Maximum system error: ±0.16° Cb

Pt1000:

Offset (typical): ±0.003° C
Offset (maximum): ±0.03° C
RMS noise: 0.003° C
Temperature resolution: 0.0002° C
Maximum system error: ±0.08° Cb

Warm-up time
MEASURpoint:
RTD sensors and external calibration
resistors:

1 hour
1 minute

a. Includes the A/D reference and gain errors.
b. Includes a maximum linearity error of 10 ppm and a calibration setup error of 10 ppm. Users must beaware that subtle resistor value tolerances and self-heating of the external calibration resistors contributecalibration setup errors.

130

Specifications

Voltage Measurement Specifications
Table 17 lists the voltage measurement specifications for the DT8871, DT8871U, DT8872,
DT8873, and DT8874 instruments.

Table 17: Voltage Measurement Specifications
FeatureSpecifications

Input voltage range (no compensation)
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:±0.0750 V±1.2500 V±1.2500 V±10 V or ±60 V (software selectable)aA/D converter resolution

24-bits

Voltage resolution
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:

0.015 V
0.3 V0.3 V1.2 V for the ±10 V input range;
12 V for the ±60 V input rangea

Sample rate

10 Samples/s

Input impedance
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:

5 Mtypical
5 Mtypical> 100 M
> 1 M (Power ON or OFF)

Input common mode voltage

60 VDC, 30 VAC

Common mode rejection @ 60 Hz and 50 Hz> 150 dB

Coupling

DC

System linearity
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:±0.005%±0.005%±0.001%±0.001%

System gain error (includes all noise sources; gain = 1)
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:±0.00075% of full-scale range±0.00075% of full-scale range±0.00075% of full-scale range±0.01% of reading

System zero error (includes all noise sources;
no filter)
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:

0.25 V RMS
5 V RMS±12 V±300 V for the ±10 V input range;±2 mV for the ±60 V input rangea

131Appendix A
Table 17: Voltage Measurement Specifications (cont.)
FeatureSystem drift error, zeroDT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:

Specifications±0.02 V/C typical±0.02 V/C typical±0.10 V/C±0.5 V/C for the ±10 V input range;±5 V/C for the ±60 V input rangea

System drift error, gain
DT8871U and DT8874 thermocouple channels:
DT8871:DT8872 and DT8874 RTD channels:
DT8873 and DT8874 voltage channels:±4 ppm/C±4 ppm/C±10 ppm/C±15 ppm/C

A/D reference
Drift:
Drift per year:±8 ppm/C maximum±100 ppm typicalFull-scale long-term stability
DT8871U and DT8874 thermocouple channels:±100 ppm/year typical

DT8871:±100 ppm/year typical

DT8872 and DT8874 RTD channels:±0.05C per year @ 0 C (±0.27C peryear @ full-scale temperature)

DT8873 and DT8874 voltage channels:±100 ppm/year typical

MEASURpoint warm-up time

1 houra. For the ±60 V range, no more than 30 Vrms, 42.4 Vpk, 60 VDC is allowed.

132

Specifications

Isolation and Protection Specifications
Table 18 lists the isolation and protection specifications for the analog input subsystem on the
DT8871, DT8871U, DT8872, DT8873, and DT8874 instruments.

Table 18: Isolation and Protection Specifications
FeatureSpecifications

DT8871U, DT8871, and DT8874 Thermocouple Channels Overvoltage
Protection (Power On/Off)Pin 2 referenced to pin 3:
Pin 2 and 3 referenced to earth ground:±40 V
30 VAC, 42.4 Vpk, 60 VDC max.a

DT8872 and DT8874 RTD Channels Overvoltage Protection (Power
On/Off)Pin 1 referenced to pin 4:
Pin 2 referenced to pin 4:
Pin 3 referenced to pin 4:
Pin 1, 2, or 3 referenced to earth ground:

±4 Vb
±40 V
±20 V
30 VAC, 42.4 Vpk, 60 VDC max.a

DT8873 and DT8874 Voltage Input Channels Overvoltage Protection(Power On/Off)
Pin 1 referenced to pin 3:
Pins 1 and 3 referenced to earth ground:

30 VAC, 42.4 Vpk, 60 VDC max.a
30 VAC, 42.4 Vpk, 60 VDC max.a

ESD protection per standard EN6100-4-2:2009 (see page 137 for more)
Arc:
Contact:

8 kV
4 kV

Isolation voltage to the host computer

30 VAC, 42.4 Vpk, 60 VDC max.a

Channel-to-channel isolation

30 VAC, 42.4 Vpk, 60 VDC max.aa. These pins are functionally isolated for a maximum of 30 VAC, 60 VDC Ch-Earth, verified by a 500 Vpk withstand.
b. Determined by internal protection diodes to the power supply. No damage occurs if current is limited to ±10 mA.

133

Appendix A

Memory Specifications
Table 19 lists the memory specifications for the analog input subsystem on the DT8871,
DT8871U, DT8872, DT8873, and DT8874 instruments.

Table 19: Memory Specifications
FeatureSpecifications

Data memory onboard

4 MByteFor Data logger built in, maximum time
before old data is overwrittena
48 channels @ 10 Hz:
48 channels @ 1 Hz:
48 channels @ 0.1 Hz:

30 minutes
5 hours
50 hours

a. Assumes limit detection is off for all channels, and for thermocouple channels,
assumes CJC data is not collected. If power fails, all temperature data in thesystem is lost. The channel input type and filter settings are still available after
power on, but the channel and digital I/O labels and channel limits are lost.

134

Specifications

Digital I/O Specifications
Table 20 lists the specifications for the digital input (DIN) and digital output (DOUT)
subsystems on the DT8871, DT8871U, DT8872, DT8873, and DT8874 instruments.

Table 20: Digital I/O Specifications
FeatureSpecifications

Number of digital I/O lines

16 (8 In, 8 Out)

Number of ports

2, 8-bit (1 In, 1 Out)

Inputs
Input type:High input voltage:Low input voltage:
High input current:
Low input current:
TerminationDC+3 to +28 V< +1.5 V
2.2 kresistor to 1.2 V
2.2 kresistor to 1.2 V
Series 2.2 k

Outputs
Output type:Output driver:High output:
Low output:
Breakdown voltage:
Contact impedance:

Solid-state relay
CMOS± 30 V
0.4 V @ 400 mA± 60 V1

Isolation voltage
To computer ground:
Channel to channel:

30 VAC, 42.4 Vpk, 60 VDC max.a
30 VAC, 42.4 Vpk, 60 VDC max.aa. These pins are functionally isolated for a maximum of 30 VAC, 60 VDC Ch-Earth,verified by a 500 Vpk withstand.

135

Appendix A

Power, Physical, and Environmental Specifications
Table 21 lists the power, physical, and environmental specifications for the DT8871, DT8871U,
DT8872, DT8873, and DT8874 instruments.

Table 21: Power, Physical, and Environmental Specifications
FeatureExternal power requirements+5 V ±0.25V @ 2 A (0.9 mA typical)

PhysicalDimensions of enclosure:88.14 (H) x 212.85 mm (W) x 211.43 mm (D)Weight:Environmental
Operating temperature range:
Storage temperature range:
Relative humidity:
Altitude:
Pollution degree:

136

Specifications

1704 gIndoor use only
0C to55C–25C to 85C
10 to 90%, noncondensing
up to 2000 m
2

Specifications

Regulatory Specifications
The DT8871, DT8871U, DT8872, DT8873, and DT8874 instruments are CE-compliant. Table 22
lists the regulatory specifications for the DT8871, DT8871U, DT8872, DT8873, and DT8874
instruments.

Table 22: Regulatory Specifications
FeatureSpecifications

Emissions (EMI)FCC Part 15, Class A
EN 55011:2009/A1:2010 (CISPR 11:2009/A1:2010), Group 1, Class A

Immunity

EN 61326-1:2013 (IEC 61326-1:2012), Class A
Electrical Equipment for Measurement, Control, and Laboratory Use
EMC Requirements
EN61000-4-2:2009
Electrostatic Discharge (ESD) 4 kV contact discharge,
8 kV air discharge, 4 kV horizontal and vertical coupling planes
EN61000-4-3:2006
Radiated electromagnetic fields, 3 V/m, 80 to 1000 MHz;
3 V/m, 1.4 GHz to 2 GHz; 1 V/m, 2 GHz to 2.7 GHz
EN61000-4-4:2004
Electrical Fast Transient/Burst (EFT) 1 kV on data cables
EN61000-4-6:2009
Conducted immunity requirements, 3 Vrms on data cables
150 kHz to 80 MHz

RoHS (EU Directive 2011/65/EU)

Compliant (as of July 1st, 2006)137

Appendix A

Connector Specifications
This section lists the specifications for the following connector types:• Thermocouple connectors• RTD connectors• Voltage connectors• Ethernet connector

Thermocouple Connectors
Table 23 lists the specifications for the thermocouple connectors used on the DT8871,
DT8871U, and DT8874 instruments.

Table 23: Thermocouple Connector Specifications
FeatureThermocouple jacks

Specifications
Omega plugs
SMPW-U-M – For voltage measurements
SMPW-J-M – For J thermocouple type
SMPW-K-M – For K thermocouple type
SMPW-T-M – For T thermocouple type
SMPW-E-M – For E thermocouple type
SMPW-S-M – For S thermocouple type
SMPW-R-M – For R thermocouple type
SMPW-B-M – For B thermocouple type
SMPW-N-M – For N thermocouple type

Thermocouple connector

Omega part# PCC-SMP-U-100-R-CE-ROHS

CAUTION:
When connecting inputs to the thermocouple connectors on a
MEASURpoint or TEMPpoint instrument, it is highly recommended
that you use only original Omega thermocouple plugs (SMPW), as
connectors from other suppliers may not be equivalent mechanically.
If you use connectors from suppliers other than Omega, there is arisk that you may mechanically damage the thermocouple
connectors on the MEASURpoint or TEMPpoint instrument.

138

Specifications

RTD Connectors
Table 24 lists the specifications for the RTD connectors used on the DT8872 and DT8874
instruments.

Table 24: RTD Connector Specifications
FeatureSpecifications

4-Position screw terminal block header

Phoenix Contact 1803293

4-Position screw terminal block plug

Phoenix Contact 1803594

Voltage Connectors
Table 25 lists the specifications for the voltage connectors used on the DT8873 and DT8874
instruments.

Table 25: Voltage Connector Specifications
FeatureSpecifications

4-Position screw terminal block header

Phoenix Contact 1803293

4-Position screw terminal block plug

Phoenix Contact 1803594

Ethernet (RJ45) Connector
The Ethernet (RJ45) connector used on the DT8871, DT8871U, DT8872, DT8873, and DT8874
instruments is shown in Figure 44.

Figure 44: Ethernet (RJ45) Connector

139Appendix A
The pin assignments of this connector are described in Table 26:

Table 26: Ethernet Connector Pin Assignments
Pin

Signal Name

Description

1

TXD+

Transmit Data+

2

TXD

Transmit Data

3

RXD+

Receive Data+

4

EPWR+

Power from Switch+

5

EPWR+

Power from Switch+

6

RXD

Receive Data

7

EPWR

Power from Switch

8

EPWR

Power from SwitchNote: DT8871, DT8871U, DT8872, DT8873, and DT8874 instruments do not support
Auto-MDIX.

140

Specifications

External Power Supply Specifications
Table 27 lists the specifications for the EP361 +5 V external power supply that is used with theDT8871, DT8871U, DT8872, DT8873, and DT8874 instruments.

Table 27: External Power Supply (EP361) Specifications
FeatureSpecifications

Type

Total Power medical power supply (TPES22-050400 or
TPEMG24-S050400-7)

Input voltage

Typical 90 - 264 V AC

Input current
TPES22-050400

Typical 0.38 A at 115 V AC, 0.15 A at 230 V AC

TPEMG24-S050400-7

Typical 0.347 A at 115 V AC, 0.215 A at 230 V AC

Frequency

47 to 63 Hz

Inrush current
TPES22-050400

35 A at 230 V AC typical or less than 30 A by adding
thermistor

TPEMG24-S050400-7

6.274 A RMS at 230 V AC

Output voltage

5 V DC

Output current

4.0 A

Output wattage
TPES22-050400

Typical 22 - 24 W

TPEMG24-S050400-7

Typical 20 - 24 W

Noise and ripple

1% peak to peak

Regulatory specifications
TPES22-050400

UL, N, CE, FCC Class B

TPEMG24-S050400-7

UL, ITE, CE, FCC Class B, Energy Star compliant141

Appendix A

142

B
Connector Pin Assignments

143

Appendix B
Table 28 lists the pin assignments for the 37-pin digital I/O connector on TEMPpoint,
VOLTpoint, and MEASURpoint instruments.

Table 28: Digital I/O Connector Pin Assignments
Pin

144

Description

Pin

Description

1

Digital Input 0+–2

Digital Input 1+

20

Digital Input 0–

3

Digital Input 2+

21

Digital Input 1–

4

Digital Input 3+

22

Digital Input 2–

5

Digital Input 4+

23

Digital Input 3–

6

Digital Input 5+

24

Digital Input 4–

7

Digital Input 6+25

Digital Input 5–

8

Digital Input 7+

26

Digital Input 6–

9

Not Connected

27

Digital Input 7–

10

Digital Output 0

28

Not Connected

11

Digital Output 1

29

Digital Output 0

12

Digital Output 2

30

Digital Output 1

13

Digital Output 3

31

Digital Output 2

14

Digital Output 4

32

Digital Output 3

15

Digital Output 5

33

Digital Output 4

16

Digital Output 6

34

Digital Output 5

17

Digital Output 7

35

Digital Output 6

18

Not Connected

36

Digital Output 7

19

Not Connected37

Not Connected

C
Configuring Network Settings onYour PC
Configuring the PC to Use Auto-IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Specifying a Static IP Address for your Instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Reconfiguring the PC to Use a Static IP Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

145

Appendix C

Configuring the PC to Use Auto-IP
To set up the a TEMPpoint, VOLTpoint, or MEASURpoint instrument when the LAN does notsupport a DHCP server and your PC is configured to use a static IP address, you must
temporarily reconfigure the PC to use Auto-IP by performing the following steps:

Note: This procedure may differ slightly depending on your computer and the version of
Windows you are using. Windows XP instructions are shown here.

1. From the Windows Start menu, click Settings, and then click Network Connections.
2. Right-click Local Area Connection, and select Properties.

3. In the General tab window, double-click Internet protocol (TCP/IP). (If a TCP/IP
selection is not listed, click Install, select Protocol, click Add, select the TCP/IP protocol,and click Install, and repeat step 3).

146

Configuring Network Settings on Your PC

4. IMPORTANT: Write down the IP address and subnet mask that is displayed! You willneed this information later.
5. Select Obtain an IP address automatically, and then click OK.

6. Select the Alternate Configuration tab, and ensure that Automatic private IP address isselected.

147

Appendix C

7. Renew the IP address of the computer. From the Windows Start menu, click Settings->Network Connections -> Local Area Connection -> Support -> Repair.
Or, if you prefer to do this from the command prompt window, click Run from theWindows Start menu, enter cmd, and click OK to bring up the command prompt window.
Then, from the command prompt window, enter:
ipconfig /renew
ipconfig /all148

renews the IP address
checks the IP addressConfiguring Network Settings on Your PC

Specifying a Static IP Address for your Instrument
To specify a static IP address for your TEMPpoint, VOLTpoint, or MEASURpoint instrument,
use the LAN Configuration page of the web interface as follows:
1. From the LAN Configuration page, click Modify.
2. Specify the username as sysadmin, and specify the password (the default password isuser). You can change the password, if you desire.
3. Uncheck the checkbox called Automatic private IP address enabled.
4. Click Static.
5. Specify a static IP address for the instrument, so that is will be on the same subnet as yourPC:

Note: You need a Simple Network Time Protocol (SNTP) time server on the LAN; otherwise,
you need to provide a gateway. See your network administrator for more details.

149

Appendix C

Reconfiguring the PC to Use a Static IP Address
After you have set up your instrument, you can reconfigure your PC to use a static IP addressusing this procedure:
1. From the Windows Start menu, click Settings, and then click Network Connections.
2. Right-click Local Area Connection, and select Properties.
3. In the General tab window, double-click Internet protocol (TCP/IP).
4. Select Use the following IP address:, specify the static IP address and subnet mask thatwas initially assigned to the PC (see page 146), and click OK.

5. Renew the IP address of the computer. From the Windows Start menu, click Settings->Network Connections -> Local Area Connection -> Support -> Repair.
Or, if you prefer to do this from the command prompt window, click Run from theWindows Start menu, enter cmd, and click OK to bring up the command prompt window.
Then, from the command prompt window, enter:
ipconfig /renew
ipconfig /all150

renews the IP address
checks the IP addressIndexIndex
Aaccessories 22
accuracy specifications, thermocouple 124, 126
Active Scripting 70
activity, Ethernet LED 42
address string 41
Agilent VISA 31
alarm limit configuration 84
alias, VISA 41
alpha curves 128
analog input 101
basic instrument specifications 122
calibration 106
channels 101
CJC circuit 103
configuration 80
conversion modes 108
data format for RTD channels 110
data format for thermocouple channels 110
data format for voltage channels 111
differential configuration 49, 51
error conditions 111
filtering 110
input ranges 104
open thermocouple detection 103
out of range data 105, 106
resolution 106
RTD specifications 128
RTD types 104
sample clock 107
thermocouple specifications 123
thermocouple types 102
trigger source 107
wiring current loop inputs to RTD channels 62
wiring current loop inputs to thermocouple
channels 60
wiring current loop inputs to voltage channels 63
wiring RTD inputs 51
wiring thermocouple inputs 49
wiring voltage inputs to RTD channels 57
wiring voltage inputs to thermocouple channels
55
wiring voltage inputs to voltage channels 58
application wiring
current loop inputs to RTD channels 62
current loop inputs to thermocouple channels 60

current loop inputs to voltage channels 63
digital inputs 65
digital outputs 66
RTD inputs 51
thermocouple inputs 49
voltage inputs to RTD channels 57
voltage inputs to thermocouple channels 55
voltage inputs to voltage channels 58
applying power 39
associating CSV files 74
attaching the module to the computer 35
Auto-IP 37, 41, 146

Bblock diagrams 96
DT8871 97
DT8871U 96
DT8872 98
DT8873 99
DT8874 100

Ccables 36
crossover 38
standard LAN (EP372) 37
calibration 106
channel-to-channel functional isolation 113
CJC circuit 103
clients 69
clocks, analog input 107
cold junction compensation 103
configuring
alarm limits 84
analog input channels 80
digital inputs 85
digital outputs 86
filters 83
LAN 79scan rate 82
triggers 85
configuring network settings on PC 145
connecting signals
current loop inputs to RTD channels 62
current loop inputs to thermocouple channels 60
current loop inputs to voltage channels 63

151

Index
digital inputs 65
digital outputs 66
RTD inputs 51
thermocouple inputs 49
voltage inputs to RTD channels 57
voltage inputs to thermocouple channels 55
voltage inputs to voltage channels 58
connecting to the LAN 35
private LAN 37
site LAN 36
connector pin assignments
digital I/O connector 143
Ethernet connector 140
continuous analog input 108
conversion modes 108
continuous analog input (scan mode) 108
digital I/O 113
simultaneous single-value analog input 108
conversion rate 109
crossover cable 38
CSV files 74
customer service 119

Ddata encoding 110
data format
RTD channels 110
thermocouple channels 110
voltage channels 111
DHCP server 36, 37, 41
differential channels 49, 51
digital I/O
channel-to-channel functional isolation 113
connecting input signals 65
connecting output signals 66
connector pin assignments 143
controlling the outputs 88
input configuration 85
lines 112, 113
operation modes 113
output configuration 86
reading the digital input port in the analog data
stream 108
reading the inputs 90
resolution 113
specifications 135
subsystem specifications 135
digital trigger 107
discovery utility, Eureka 19, 31, 75
DNS server 41

152

downloading measurements 91

E
encoding data 110
ENet Activity LED 42
ENet Link LED 42
environmental specifications 136
EP333 cable assembly 22, 64
EP372 LAN cable 37
EP373 single rack mount kit 22
EP374 dual rack mount kit 22
error conditions 111
Ethernet activity 42
Ethernet cable 36, 37
Ethernet connector specifications 139
Ethernet crossover cable 38
Eureka Discovery Utility 19, 31
firewall settings 76
running 75
troubleshooting 76
using 75
Excel 74
using to display data 92
external digital trigger 107

Ffactory service 119
features 14
FIFO 109
filters 83, 110
floating-point data 110
formatting data
RTD channels 110
thermocouple channels 110
voltage channels 111
frequency 107

G
GMT 80H
hardware features 14high drive digital outputs 66
host name 41
hub
using with a private LAN 37
using with a site LAN 36

IndexI

N

input ranges 104
installing the software 31
prerequisites 31
instrument web interface 19
Internet Explorer browser settings 69
JavaScript 70
pop-up blockers 73
security levels 70
Internet zone 70
Intranet zone 71
IP address 41
isolation 113
isolation specifications 133
IVI-COM driver 21

network settings 145
NI-VISA 31
Notepad 74

JO
open thermocouple detection 103
operation modes
continuous analog input (scan mode) 108
digital I/O 113
simultaneous single-value analog input 108
OPN LED 42, 103, 105
opto-isolators 112
out of range data
RTD channels 106
thermocouple channels 105
voltage channels 106

Java 69

LLAN
configuration 79
connecting to a private LAN 37
connecting to a site LAN 36
LED 42
launching the web interface 78
LEDs
ENet Activity 42
ENet Link 42
LAN 42
LMT 42, 105, 106
OPN 42, 103, 105
Power 39
USB 42
limit configuration 84
lines, digital I/O 112, 113
LMT LED 42, 105, 106M
Measurement Instrument Calibration Utility 21
mechanical relays, controlling 66
memory specifications 134
Microsoft Excel 74
Microsoft Notepad 74
moving average filter 110

P
password 80
physical specifications 136
pinging the instrument 116, 117
pop-up blockers 73
power
applying 39
specifications 136
prerequisite software 31
private LAN 37
connecting directly to a computer 38
connecting using a hub or switch 37
protection specifications 133

Q
QuickDAQ
Advanced FFT Analysis option 20
Base version 19
FFT Analysis option 20

Rrack mounting 22
raw filter 110
recommendations for wiring 47
regulatory specifications 137
requirements 30
requirements for web interface 69
associating CSV files 74
Internet Explorer browser settings 69

153

IndexJava 69
Reset pin 42, 44
resetting the instrument 44
resolution
analog input 106
digital I/O 113
returning boards to the factory 119
RJ45 connector specifications 139
RMA 119router, using with a site LAN 36
RTD alpha curves 128
RTD channels
data format 110
RTD connections
2-wire 53
3-wire 53
4-wire 52
RTD connector specifications 139
RTD specifications 128
RTD types 104

S
sample clock 107
sample rate 109
scan rate 82
SCPI
clients 69
programming 21
security levels 70
Internet zone 70
Intranet zone 71
Trusted Site zone 72
SENSOR_IS_OPEN 104
simultaneous single-value analog input 108
site LAN 36
connecting using a hub, switch, or router 36
connecting without using a hub, switch, or router
37
software trigger 107
solid-state relays 113
controlling 66
sourcing 66
specifications 121, 145
basic instrument 122
digital I/O 135
environmental 136
Ethernet connector 139
external power supply 141
isolation and protection 133
memory 134

154

physical 136
power 136
regulatory 137
RJ45 connector 139
RTD 128
RTD connectors 139
system temperature error 124, 126
temperature 129
thermocouple 123
thermocouple connectors 138
voltage connectors 139
voltage measurement 131
static IP addresses 80, 146, 150
STP37 screw terminal panel 22, 64
switchusing with a private LAN 37
using with a site LAN 36
system requirements 30
system temperature error 124, 126

T
TCP/IP configuration 41
technical support 118
temperature error 124, 126
temperature specifications 129
thermocouple accuracy specifications 124, 126
thermocouple channels
data format 110
thermocouple connector specifications 138
thermocouple types 102
trademark and copyright information 2
trigger source 107
external 107
software 107
triggers 85
troubleshooting
procedure 116
technical support 118
troubleshooting table 116
Trusted Site zone 72

U
unpacking 29
USB LED 42
username 80
UTC 80IndexV
VISA alias 41
VISA resource string 41
voltage connector specifications 139
voltage measurement specifications 131
VXI-11 clients 69

Wwarm-up time 48
web interface 19, 78
alarm limit configuration 84
analog input channel configuration 80
clients 69
controlling the digital outputs 88
digital input and trigger configuration 85
digital output configuration 86
downloading measurements 91
filter configuration 83
LAN configuration 79
measurement and controlling the instrument 87
reading the digital inputs 90
requirements for using 69
scan rate configuration 82
starting and stopping a scan 87
wiring signals
current loop inputs to RTD channels 62
current loop inputs to thermocouple channels 60
current loop inputs to voltage channels 63
digital inputs 65
digital outputs 66
recommendations 47
RTD inputs 51
thermocouple inputs 49
voltage inputs to RTD channels 57
voltage inputs to thermocouple channels 55
voltage inputs to voltage channels 58
warm-up time 48

Z
zones
Internet 70
Intranet 71
Trusted Site 72

155Index156