Rockwell Automation AB quality Allen-Bradley 1746-INT4 User manual

Thermocouple/mV
Isolated Input
Module
Catalog Number 1746-INT4
User Manual

Important User Information
Solid state equipment has operational characteristics differing from those of
electromechanical equipment. Safety Guidelines for the Application,
Installation and Maintenance of Solid State Controls (publication SGI-1.1
available from your local Rockwell Automation sales office or online at
http://literature.rockwellautomation.com) describes some important
differences between solid state equipment and hard-wired electromechanical
devices. Because of this difference, and also because of the wide variety of
uses for solid state equipment, all persons responsible for applying this
equipment must satisfy themselves that each intended application of this
equipment is acceptable.
In no event will Rockwell Automation, Inc. be responsible or liable for
indirect or consequential damages resulting from the use or application of
this equipment.
The examples and diagrams in this manual are included solely for illustrative
purposes. Because of the many variables and requirements associated with
any particular installation, Rockwell Automation, Inc. cannot assume
responsibility or liability for actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to
use of information, circuits, equipment, or software described in this manual.
Reproduction of the contents of this manual, in whole or in part, without
written permission of Rockwell Automation, Inc., is prohibited.
Throughout this manual, when necessary, we use notes to make you aware
of safety considerations.
Allen-Bradley, SLC 500, SLC, RSLogix 500, TechConnect, Rockwell Automation, ControlLogix, and RSLinx are trademarks of
Rockwell Automation, Inc.
Trademarks not belonging to Rockwell Automation are property of their respective companies.
WARNING Identifies information about practices or circumstances that can cause
an explosion in a hazardous environment, which may lead to personal
injury or death, property damage, or economic loss.
IMPORTANT Identifies information that is critical for successful application and
understanding of the product.
ATTENTION Identifies information about practices or circumstances that can lead
to personal injury or death, property damage, or economic loss.
Attentions help you identify a hazard, avoid a hazard, and recognize
the consequence
SHOCK HAZARD Labels may be on or inside the equipment, for example, a drive or
motor, to alert people that dangerous voltage may be present.
BURN HAZARD Labels may be on or inside the equipment, for example, a drive or
motor, to alert people that surfaces may reach dangerous
temperatures.

3Publication 1746-UM614B-EN-P - September 2007
Table of Contents
Preface
Use This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Who Should Use This Manual . . . . . . . . . . . . . . . . . . . . . . . . 7
Purpose of This Manual. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Additional Resources. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Common Techniques Used in this Manual . . . . . . . . . . . . . . . 8
Chapter 1
Module Overview
Compliance with European Union Directives . . . . . . . . . . . . . 9
General Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
System Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Block Diagram of Isolated-Channel Input Circuits. . . . . . . . . 15
Chapter 2
Quick Start
Required Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Channel Configuration Worksheet . . . . . . . . . . . . . . . . . . . . 22
Chapter 3
Install and Wire the Module
Electrostatic Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Power Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Module Installation and Removal . . . . . . . . . . . . . . . . . . . . . 27
Wire the Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Install the Ferrite Collar . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Chapter 4
Preliminary Operating
Considerations
Module ID Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Module Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Input Channel Characteristics. . . . . . . . . . . . . . . . . . . . . . . . 38
Response to Slot Disabling . . . . . . . . . . . . . . . . . . . . . . . . . 40
Chapter 5
Access Files to Configure I/O
Click and Drag Configuration . . . . . . . . . . . . . . . . . . . . . . . 41
Read IO Config Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Chapter 6
Channel Configuration, Data, and
Status
Channel Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Channel Configuration Procedure . . . . . . . . . . . . . . . . . . . . 50
Use Channel Data Words. . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Use Channel Status Words. . . . . . . . . . . . . . . . . . . . . . . . . . 53

Publication 1746-UM614B-EN-P - September 2007
4Table of Contents
Chapter 7
Ladder Programming Examples
Processor Basics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Load Channel Configurations for Transfer to the Module . . . 58
Change a Channel Configuration . . . . . . . . . . . . . . . . . . . . . 59
Verify Changes to a Channel Configuration . . . . . . . . . . . . . 61
Process a Channel Input with the PID Instruction. . . . . . . . . 62
Monitor Channel Status Bits. . . . . . . . . . . . . . . . . . . . . . . . . 63
Chapter 8
Module Diagnostics and
Troubleshooting
Module and Channel Diagnostics. . . . . . . . . . . . . . . . . . . . . 65
LED Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Replacement Parts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Contacting Rockwell Automation . . . . . . . . . . . . . . . . . . . . . 70
Chapter 9
Application Programming
Examples
Basic Example
(to display a temperature) . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Supplementary Example (select display in °C or °F) . . . . . . . 73
Appendix A
Module Specifications
Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Physical Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Environmental Specifications . . . . . . . . . . . . . . . . . . . . . . . . 80
Input Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Appendix B
Channel Configuration
Worksheets
Appendix C
Thermocouple Descriptions
J Type Thermocouple
(iron versus copper-nickel <Constantan>) . . . . . . . . . . . . . . 97
K Type Thermocouple (nickel-chromium versus
nickel-aluminum) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
T Type Thermocouple (copper versus copper-nickel
<Constantan>) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
E Type Thermocouple (nickel-chromium versus
copper-nickel <Constantan>). . . . . . . . . . . . . . . . . . . . . . . 100
S and R Type Thermocouple S (platinum-10% rhodium
versus platinum)
R (platinum-13% rhodium versus platinum) . . . . . . . . . . . . 101
C and D Type Thermocouples
C (tungsten-5% rhenium versus tungsten-26% rhenium)
D (tungsten-3% rhenium versus tungsten-25% rhenium) . . . 102

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Table of Contents 5
Appendix D
Channel Calibration
About the Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Appendix E
CSA Hazardous Location Approval
Glossary
Index

Publication 1746-UM614B-EN-P - September 2007
6Table of Contents

7Publication 1746-UM614B-EN-P - September 2007
Preface
Use This Manual
Read this preface to familiarize yourself with the rest of the manual.
This preface covers the following topics:
•Who should use this manual
•The purpose of this manual
•Terms and abbreviations
•Conventions used in this manual
•Allen-Bradley support
Who Should Use This
Manual
Use this manual if you are responsible for designing, installing,
programming, or troubleshooting control systems that use
Allen-Bradley small logic controllers.
You should have a basic understanding of SLC 500 products. You
should understand programmable controllers and be able to interpret
the ladder logic instructions required to control your application. If
you do not, contact your local Allen-Bradley representative for
information on available training courses before using this product.
Purpose of This Manual
This manual is a reference guide for the module. The manual:
•gives you an overview of system operation.
•explains the procedures you need to install and wire the module
at the application site.
•provides ladder programming examples.
•provides an application example of how this input module can
be used to control a process.

Publication 1746-UM614B-EN-P - September 2007
8Preface
Additional Resources
The following documents contain information that may be helpful to
you as you use Allen-Bradley SLC products. To obtain a copy of any
of the Allen-Bradley documents listed, contact your local
Allen-Bradley office or distributor.
Common Techniques Used
in this Manual
The following conventions are used throughout this manual:
•Bulleted lists such as this one provide information, not
procedural steps.
•Numbered lists provide sequential steps or hierarchical
information.
•Text in this font indicates words or phrases you should type.
Resource Description
SLC 500 Systems Selection Guide, publication 1747-SG001 An overview of the SLC 500 family of products
SLC 500 Module Hardware Style User Manual, publication
1747-UM011 A description on how to install and use your modular SLC 500
programmable controller
Installation & Operation Manual for Fixed Hardware Style
Programmable Controllers, publication 1747-6.21 A description on how to install and use your fixed SLC 500
programmable controller
SLC 500 Instruction Set Reference Manual, publication
1747-RM001 A reference manual that contains status file data, instruction set,
and troubleshooting information about the software
SLC 500 4-Channel Analog I/O Modules User’s Manual, publication
1746-UM005 A resource manual and user’s guide containing information about
the analog modules used in your SLC 500 system.
Industrial Automation Wiring and Grounding Guidelines, publication
1770-4.1 In-depth information on grounding and wiring Allen-Bradley
programmable controllers
Application Considerations for Solid-State Controls. publication
SGI-1.1 A description of important differences between solid-state
programmable controller products and hard-wired
electromechanical devices
National Electrical Code, published by the National Fire Protection
Association of Boston, MA An article on wire sizes and types for grounding electrical equipment

9Publication 1746-UM614B-EN-P - September 2007
Chapter 1
Module Overview
This chapter describes the thermocouple/millivolt isolated input
module and explains how the SLC controller reads thermocouple or
millivolt analog input data from the module. The following
information is included:
•Compliance with European Union Directives
•General description and hardware features
•An overview of system and module operation
•Block diagram of channel input circuits
Compliance with European
Union Directives
If this product has the CE mark, it is approved for installation within
the European Union and EEA regions. It has been designed and tested
to meet the following directives.
EMC Directive
This product is tested to meet Council Directive 89/336/EEC
Electromagnetic Compatibility (EMC) and the following standards, in
whole or in part, documented in a technical construction file:
•EN 50081-2EMC — Generic Emission Standard, Part 2 —
Industrial Environment
•EN 50082-2EMC — Generic Immunity Standard, Part 2 —
Industrial Environment
This product is intended for use in an industrial environment.
Low Voltage Directive
This product is tested to meet Council Directive 73/23/EEC Low Voltage,
by applying the safety requirements of EN 61131–2 Programmable
Controllers, Part 2 — Equipment Requirements and Tests.
For specific information required by EN 61131-2, see the appropriate
sections in this publication, as well as the Industrial Automation
Wiring and Grounding Guidelines (for noise immunity), publication
1770-4.1.
This equipment is classified as open equipment and must be mounted
in an enclosure during operation to provide safety protection.

Publication 1746-UM614B-EN-P - September 2007
10 Module Overview
General Description
The module stores digitally-converted thermocouple and/or millivolt
(mV) analog data in its image table for retrieval by all fixed and
modular SLC 500 processors. The module supports connections from
any combination of up to four thermocouple and/or mV analog
sensors.
Input Ranges
The following tables define thermocouple types and associated
temperature ranges and the millivolt analog-input signal ranges that
each of the module’s input channel supports.
Refer to the specifications in Appendix A to determine the practical
temperature range of your thermocouple.
Each input channel is individually configurable for a specific input
device, and provides open-circuit, over-range, and under-range
detection and indication.
Thermocouple Temperature Ranges
Type °C Temperature Range °F Temperature Range
C0…2317 32… 4201
D0… 2317 32…4201
J-210…760 -346…1400
K-270…1370 -454…2498
T-270…400 -454…752
B300…1820 572…3308
E-270…1000 -454…1832
R0…1768 32…3214
S0…1768 32…3214
N0…1300 32…2372
CJC Sensor 0…85 32…185
Millivolt Input Ranges
-50…50 mV
-100…100 mV

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Module Overview 11
Hardware Features
The module fits into any single slot for I/O modules in either an SLC
500 modular system or an SLC 500 fixed system expansion chassis
(1746-A2). It is a Class 1(1) module (uses eight input words and eight
output words).
The module contains a removable terminal block providing
connections for four thermocouple and/or analog input devices.
There are two cold-junction compensation (CJC) sensors that
compensate for the cold-junction at ambient temperature rather than
at freezing 0 °C (32 °F). There are no output channels on the module.
You configure the module with software rather than with jumpers or
switches.
Hardware Features
(1) Requires use of Block Transfer in a remote I/O configuration.
INPUT
CJCA+
CHL3±
CHL3+
CHL2±
CHL2+
CHL1±
CHL1+
CHL0±
CHL0+
Do Not
Remove
CJCA±
Do Not
Remove
CJCB±
Do Not
Remove
CJCB+
Do Not
Remove
MODULE ST ATUS
0
1
2
3
CHANNEL
ST ATUS
THERMOCOUPLE/mV
ISOLA TED
ISOLA TED THERMOCOUPLE / mV INPUT MODULE
Do Not
Connect
Do Not
Connect
Do Not
Connect
Do Not
Connect
Do Not
Connect
Do Not
Connect
Side Label
Self-locking Tabs
Do not connect to
this terminal.
Cable Tie Slots
CJC Sensors
Removable
Terminal Block
Module Status
LED (Green)
Channel Status
LED Indicators
(Green)
Door Label
Hardware Features
Hardware Function
Channel status LED indicators Display operating and fault status of
channels 0, 1, 2, and 3
Module status LED Displays operating and fault status of the
module
Side label (nameplate) Provides module information
Removable terminal block Provides electrical connection to input
devices
Door label Permits easy terminal identification
Cable tie slots Secure input wiring at the module
Self-locking tabs Secure module in chassis slot

Publication 1746-UM614B-EN-P - September 2007
12 Module Overview
Diagnostic LED Indicator
The module contains diagnostic LED indicator that help you identify
the source of problems that may occur when cycling power or during
normal operation.
Power cycling and channel diagnostics are explained in Chapter 8,
Module Diagnostics and Troubleshooting.
System Overview
The module communicates with the SLC 500 processor and receives
+5V dc and +24V dc power from the system power supply through
the parallel backplane interface. No external power supply is
required. You may install as many thermocouple modules in the
system as the power supply can support.
Module Placement
Each module channel can receive input signals from a thermocouple
or a millivolt analog input device. You configure each channel to
accept either one. When configured for thermocouple input types, the
module converts analog input voltages into cold-junction
compensated and linearized, digital temperature readings. The
module uses the National Bureau of Standards (NBS) Monograph 125
and 161 based on IPTS-68 for thermocouple linearization.
When configured for millivolt analog inputs, the module converts
analog values directly into digital counts. The module assumes that
the mV input signal is linear.
SLC Processor Thermocouple Modules

Publication 1746-UM614B-EN-P - September 2007
Module Overview 13
System Operation
When you cycle power, the module checks its internal circuits,
memory, and basic functions. During this time, the module status
indicator remains off. If the module finds no faults, it turns on its
module status indicator.
System Operation
After completing power cycle checks, the module waits for valid
channel configuration data from your SLC ladder logic program
(channel status LED indicators are off). After channel configuration
data is transferred and channel enable bits are set for one or more
channels, the module turns on its channel status LED indicators. Then
it continuously converts the thermocouple or millivolt input to a value
within the range you selected for the channel.
Each time the module reads an input channel, the module tests that
data for a fault, for example, open-circuit, over-range, or under-range
condition. If it detects such a condition, the module sets a unique bit
in the channel status word and causes the channel status indicator to
blink.
The SLC processor reads the converted thermocouple or millivolt data
from the module at the end of the program scan, or when
commanded by the ladder program. After the processor and module
determine that the data transfer was made without error, the data can
be used in your ladder program.
Module Operation
The module’s input circuitry consists of four differential analog inputs,
each with its own analog-to-digital (A/D) convertor. The A/D
convertors read the analog input signals and convert them to digital
counts. The input circuitry also continuously samples the CJC sensors
and compensates for temperature changes at the cold-junction
(terminal block).
See page 15 for a block diagram for the analog input circuitry.
Channel Data Word
Channel Status Word
Channel Configuration Word
SLC 500
Processor
Thermocouple
Input Module
Thermocouple
or mV Analog
Signals

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14 Module Overview
Module Addressing
The module requires eight words each in the SLC processor’s input
and output image tables. Addresses for the module in slot e are as
follows:
I:e.0…3 thermocouple/mV data for channels 0…3, respectively
I:e.4…7 status data for channels 0…3, respectively
O:e.0…3 configuration data for channels 0…3, respectively
O:e.4…7 reserved for future use. Do not use.
Compatibility with Thermocouple and Millivolt Devices and
Cables
The module is compatible with the following NBS MN-125 and -161
standard types of thermocouples: B, C, D, E, J, K, N, R, S, and T and
extension wire. The module is also compatible with a variety of mV
devices with an output of ±50 or ±100 mV.
Refer to Appendices A and C for details.
To minimize interference from radiated electrical noise, we
recommend twisted-pair and highly shielded cables.
Minimizing Interference Devices
For This Type of Device We Recommend This Cable (or equivalent)
Thermocouple type J EIL Corp. J20-5-502
Thermocouple type K EIL Corp. K20-5-510
Thermocouple type T EIL Corp. T20-5-502
Other thermocouple types Consult with EIL Corp or other manufacturers
Millivolt devices Alpha Suprashield XTRA-GUARD 1
5121 (1pr), 5122 (2pr), 5131 (3pr), 5141 (4pr)

Publication 1746-UM614B-EN-P - September 2007
Module Overview 15
Block Diagram of
Isolated-Channel Input
Circuits
This illustration shows a block diagram for the analog input circuitry.
Block Diagram
+
±
+
±
+
±
+
±
+
±
+
±
2
4
6
8
10
12
14
16
18
Channel 0
Wire Braid
I/O Chassis
Ground
CJCA Sensor
Terminal Block Module Circuitry
Open-circuit
Detection
Multiplexer Analog to
Digital
Converter
Analog to
Digital
Converter
Analog to
Digital
Converter
Analog to
Digital
Converter
Multiplexer
Digital Value
Channel 0 &
CJC Sensor
Signal
Digital Value
Channel 1
Digital Value
Channel 2
Digital Value
Channel 3 &
CJC Sensor
Signal
8 Hz
Digital
Filter
8 Hz
Digital
Filter
8 Hz
Digital
Filter
8 Hz
Digital
Filter
I/O Chassis
Ground
CJCB Sensor

Publication 1746-UM614B-EN-P - September 2007
16 Module Overview

17 Publication 1746-UM614B-EN-P - September 2007
Chapter 2
Quick Start
Use this chapter as an abbreviated procedure for getting the module
into operation or as an overview if you need the additional steps
described in subsequent chapters. This chapter assumes that you
understand the following things:
•SLC 500 products
•Electronic process control
•Ladder logic instructions
Because this chapter is a start-up guide, it does not contain detailed
explanations. It does, however, refer to other chapters or to other SLC
publications for more information.
If you are unsure of terms used or concepts presented in this chapter,
always read the referenced chapters before trying to apply the
information.
This chapter describes:
•what equipment you need.
•how to install and wire the module.
•how to set up one channel for thermocouple input.
•the state of the LED indicators at normal start-up.
•the channel status word.
Required Tools
Have the following tools and equipment ready:
•Medium blade screwdriver
•Medium cross-head screwdriver
•Thermocouple or millivolt sensor
•Thermocouple extension wire (if needed)
•The module
•I/O chassis
•SLC processor and power supply
•Programming software

Publication 1746-UM614B-EN-P - September 2007
18 Quick Start
Procedures
1. Unpack the module.
Unpack the module making sure that the contents include these
items:
•Module (Catalog Number 1746-INT4)
•Removable terminal block (factory-installed on module) with
CJC sensors attached
If the contents are incomplete, call your local Rockwell
Automation representative for assistance.
2. Review the power requirements of the modules drawing power
from the chassis power supply.
•The fixed, two-slot chassis supports two 1746-INT4 modules.
If combining a 1746-INT4 module with a different type of
module, refer to Considerations for a Fixed Controller in
Chapter 3.
•For a modular system, compute the total load on the system
power supply.
Refer to the procedure described in the SLC 500 Modular
Hardware Style User Manual, publication 1747-UM011, or the
SLC 500 Systems Selection Guide, publication 1747-SG001.
IMPORTANT Follow these precautions to prevent damaging the module from
electrostatic discharge:
•Before handling the module, rid yourself of electric charge by
touching a grounded object.
•Avoid touching connector terminations and circuit components.
•Keep the module in its electrostatic shielded bag when not in use.
ATTENTION Never install, remove, or wire modules with power
applied to the chassis or devices wired to the module.

Publication 1746-UM614B-EN-P - September 2007
Quick Start 19
3. Install the module.
Make sure system power is off; then insert the module into the
I/O chassis. In this example procedure, the module is inserted
into slot 1.
4. Connect thermocouple wires to channel 0 on the module’s
terminal block.
Make sure both cold-junction compensation (CJC) devices are
securely attached.
5. Configure the software to accept the module.
Type the module’s ID and assigned slot (slot 1 in this example)
into the system I/O configuration.
Top and Bottom
Module Releases
Card
Guide
CHL 0-
CHL 0+
CHL 1+
CHL
1-
Important:
Ground the thermocouple’s cable shield
to the I/O chassis with 9.5 mm (3/8 in.)
braid wire. (Refer to page 31.)
Terminal Block
CJC A
Device
Thermocouple
Wire

Publication 1746-UM614B-EN-P - September 2007
20 Quick Start
6. Set up Channel 0.
Determine the operating parameters for channel 0. This example
shows the channel 0 configuration word defined with all
defaults (0) except for the channel enable (bit 11=1). Module
assumed in slot 1. (For details on channel configuration, refer to
the configuration worksheet on page 22).
7. Program the transfer of the configuration word.
Program the transfer of the configuration word (from step 6) to
the module.
a. Using the memory map function, create integer file N10.
Integer file N10 should contain one element for each channel
used. (For this example, we used N10:0.).
b. Enter configuration parameters for channel 0 (from step 6)
into N10:0.
In this example, all of the bits of N10:0 are zero except for the
channel enable bit (N10:0/11).
c. Program a ladder logic instruction to copy the contents of
N10:0 to output word O:1.0.
O:1.1
Channel 1 Configuration W ord
Channel 2 Configuration W ord
Channel 3 Configuration W ord
W
ords 4, 6, & 7
(reserved)
Bit
15
Bit 0
W ord 1
W ord 2
W ord 3
Address
O:1.0 0000000000000000
Channel 0 Configuration Word
W
ord 0
W ord 7
Input
Type
Data Format
Open Circuit
T
emperature Units
Channel Enable
Unused
0000100000000000
Use Default Settings For:
Example Settings for Channel 0.
• Type J Thermocouple
• Engineering Units x 1
• Data Word = 0 If Open Circuit
• Degrees Celsius
O:1.2
O:1.3
O:1.7
Unused
Calibration W ord 5
•
•
•
•
•
•
SLC 500 Controller
Data Files
Input Image Output Image
(8 words)
Set this bit (11) to enable channel. Address = O.1.0/11.