Rockwell Automation 1746-BTM User Manual

Barrel Temperature
Control Module

1746-BTM

User Manual

ii

Important User Information

Because of the variety of uses for the products described in this
publication, those responsible for the application and use of this
control equipment must satisfy themselves that all necessary steps
have been taken to assure that each application and use meets all
performance and safety requirements, including any applicable laws,
regulations, codes and standards.

The illustrations, charts, sample programs and layout examples shown
in this guide are intended solely f or purpo ses of ex ample. Since t here
are many variables and requirements associated with any particular
installation, Allen-Bradley does not assume responsibility or liability
(to include intellectual property liability) for actual use based upon
the examples shown in this publication.

Allen-Bradley publication SGI-1.1, Safety Guidelines for the

Application, Installation and Maintenance of Solid-State Control

(available from your local Allen-Bradley office), describes some
important differences between solid-state equipment and
electromechanical devices that should be taken into consideration
when applying products such as those described in this publication.

Reproduction of the contents of this copyrighted publication, in whole
or part, without written permission of Rockwell Automation, is
prohibited.

Throughout this manual we use notes to make you aware of safety
considerations:

ATTENTION

Identifies information about practices or
circumstances that can lead to personal injury or
death, property damage or economic loss

!

Attention statements help you to:

• identify a haza r d

• avoid a hazard

• recognize the consequences

IMPORTANT

Allen-Bradley is a trademark of Rockwell Automation

Identifies information that is critical for successful
application and understanding of the product.

Publication 1746-UM010B-EN-P - April 2001

iii

European Communities (EC) Directive Compliance

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 the Council Directive 89/336/EC
Electromagnetic Compatibility (EMC) by applying the following
standards, in whole or in part, documented in a technical construction
file:

• EN 50081-2 EMC — Generic Emission Standard, Part 2 —

Industrial Environment

• EN 50082-2 EMC — 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 Allen-Bradley
publication Industrial Automation Wiring and Grounding Guidelines,
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-UM010 B- EN-P - April 2001

iv

Publication 1746-UM010B-EN-P - April 2001

Summary of Changes

Major changes in this revision include:

• Ladder code addresses have been changed.

• The sample ladder code in Chapter 9 has been enhanced.

• Examples outlining the mathematical relationships involved in

Startup Aggressiveness Factor and Ramp Rates have been
included in Chapter 3.

• Appendixes A and B have been omitted.

• Module specifications can be found in the 1746-BTM Installation

Instructions, Publication 1746-IN014B-EN-P.

1 Publication 1746-UM010 B- EN-P - April 2001

2 Summary of Changes

Publication 1746-UM010B-EN-P - April 2001

Preface

Using This Manual

This manual shows you how to use the Barrel Temperature Control
Module (cat. no. 1746-BTM) in an A llen- Bradley SLC sys tem fo r barrel
temperature control and other injection molding or extrusion related
temperature control applications. The manual explains how to install,
program, calibrate, and troubleshoot the BTM module.

ATTENTION

Use the 1746-BTM module in a local I/O chassis only
for barrel temperature control of injection molding
applications or extruders. Any other applications are
not supported.

!

Audience

You must be able to program and operate an Allen-Bradley SLC
programmable controller to make efficient use of this module. In
particular, you must know how to configure M0 and M1 files. For
more information, see the appropriate SLC programming manual
before you generate a program for this module.

System Compatibility

System compatibility involves data table use as well as compatibility
with a local I/O chassis and SLC processor.

Data Table

Communication between the module and processor is bi-directional.
The processor transfers output data through the output image table to
the BTM module and transfers input data from the BTM module
through the input image table. The BTM module also requires M files
for configuration and calibration values.

I/O Chassis

You can use this module with 1746-A4, -A7, -A10, -or -A13 chassis,
provided there is an SLC controller in the chassis (local system). You
can place the BTM module in any I/O slot except for the first slot
which is reserved for the processor.

1 Publication 1746-UM010 B- EN-P - April 2001

P-2 Preface

SLC Processor

The 1746-BTM module is compatible with any SLC processor that
supports M0/M1 files, such as the SLC 5/05, SLC 5/04, SLC 5/03, and
SLC 5/02 controllers.

Vocabulary

In this manual, we refer to:

• the barrel temperature control module as the “1746-BTM

module,” the “BTM module,” or as “the module”

• the programmable controller as the “SLC processor”, or “the

processor”

• a thermocouple as a “TC”

• a time-proportioned output as “TPO”

• the tuning-assisted processes as “TAP”

• proportional-integral-derivative as “PID”

• cold-junction compensation as “CJC”

Publication 1746-UM010B-EN-P - April 2001

Table of Contents

Important User Information. . . . . . . . . . . . . . . . . . . . . . . . . . ii

European Communities (EC) Directive Compliance . . . . . . . iii

EMC Directive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Low Voltage Directive . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Using This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-1

Audience. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-1

System Compatibility . . . . . . . . . . . . . . . . . . . . . . . . . . P-1

Vocabulary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . P-2

Chapter 1

Temperature Control Using a BTM Module in an SLC System 1-1

Features of the Temperature Control Module . . . . . . . . . . . 1-2

Module Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Current CV . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

TPO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2

Module Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Response to Slot Disabling . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Input response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Output response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4

Chapter 2

Avoiding Electrostatic Damage. . . . . . . . . . . . . . . . . . . . . . 2-1

European Communities (EC) Directive Compliance . . . . . . 2-2

EMC Directive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Low Voltage Directive . . . . . . . . . . . . . . . . . . . . . . . . . 2-2

Determining Power Requirements . . . . . . . . . . . . . . . . . . . 2-3

Choosing a Module Slot in a Local I/O Chassis. . . . . . . . . . 2-3

Installation considerations . . . . . . . . . . . . . . . . . . . . . . 2-3

Installing the Module. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Removing the terminal block . . . . . . . . . . . . . . . . . . . . 2-5

Wiring the Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6

Cold Junction Compensation (CJC). . . . . . . . . . . . . . . . 2-6

Wiring considerations. . . . . . . . . . . . . . . . . . . . . . . . . . 2-7

Preparing and Wiring the Cables . . . . . . . . . . . . . . . . . 2-8

Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-10

Chapter 3

Loop Operation Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Word 1, Bits 0 and 1 for Channel 1. . . . . . . . . . . . . . . . 3-1

Type of Loop Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

Word 1, Bits 2-5 for Channel 1 . . . . . . . . . . . . . . . . . . . 3-1

Enable Loop Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Word 1, Bit 6 for Channel 1 . . . . . . . . . . . . . . . . . . . . . 3-2

TC Break Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Word 1, Bits 7 and 8 for Channel 1. . . . . . . . . . . . . . . . 3-2

Loop Autotune Gains Level . . . . . . . . . . . . . . . . . . . . . . . . 3-2

Word 1, Bits 10 and 11 for Channel 1 . . . . . . . . . . . . . . 3-2

1 Publication 1746-UM010 B- EN-P - April 2001

TOC-2 Table of Contents

Barrel/Non-barrel Control . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Word 1, Bit 12 for Channel 1 . . . . . . . . . . . . . . . . . . . . 3-3

Barrel Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Non–barrel control. . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3

Switching the barrel control . . . . . . . . . . . . . . . . . . . . . 3-3

Inner/Outer Zone Selection. . . . . . . . . . . . . . . . . . . . . . . . 3-4

Word 1, Bit 13 for Channel 1 . . . . . . . . . . . . . . . . . . . . 3-4

High/Low CV Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

Words 2 and 3 for Channel 1 . . . . . . . . . . . . . . . . . . . . 3-5

TC Break Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

Word 4 or O:e.8 for Channel1 . . . . . . . . . . . . . . . . . . . 3-5

Standby Setpoint. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

Word 5 for Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . . 3-5

Heat/Cool Minimum On-times. . . . . . . . . . . . . . . . . . . . . . 3-6

Words 6 and 8 for channel 1 . . . . . . . . . . . . . . . . . . . . 3-6

Heat/Cool TPO Period . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6

Words 7 and 9 for Channel 1 . . . . . . . . . . . . . . . . . . . . 3-6

PV Rate and Associated Alarm. . . . . . . . . . . . . . . . . . . . . . 3-6

Word 10 and Alarm Bit I:e.4/05 for Channel 1. . . . . . . . 3-6

High/Low Temperature and Deviation Alarms . . . . . . . . . . 3-6

Words 11-14 for Channel 1. . . . . . . . . . . . . . . . . . . . . . 3-6

Alarm Dead Band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8

Word 15 for Channel 1. . . . . . . . . . . . . . . . . . . . . . . . . 3-8

Thermal Integrity Loss Detection . . . . . . . . . . . . . . . . . . . . 3-9

Words 16 and 17 for Channel 1 . . . . . . . . . . . . . . . . . . 3-9

Ramp Rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Words 18 for Channel 1 . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Non-barrel Autotune Disturbance Size . . . . . . . . . . . . . . . . 3-9

Word 20 for Channel 1. . . . . . . . . . . . . . . . . . . . . . . . . 3-9

Implied Decimal Point . . . . . . . . . . . . . . . . . . . . . . . . . 3-10

Configuration Block, M1 File, Loops 1-4 N10:0-100. . . . . . . 3-11

Startup Aggressiveness factor. . . . . . . . . . . . . . . . . . . . . . . 3-11

Ramp Rates. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12

Publication 1746-UM010B-EN-P - April 2001

Chapter 4

Sequence of Setting PID Gains . . . . . . . . . . . . . . . . . . . . . 4-1

Autotuning the Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2

Fine-Tuning the Loops . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

Using the PID Equation. . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Entering Autotune/Gains Values with Implied Decimal Point 4-5

PID Gains/Autotune Block, M0 File for Loops 1–4 . . . . 4-6

Table of Contents TOC-3

Chapter 5

Controlling a Loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

M1 Configuration File. . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Output Image Table. . . . . . . . . . . . . . . . . . . . . . . . . . . 5-1

Autotune a Loop. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-2

Requirements for Autotune. . . . . . . . . . . . . . . . . . . . . . 5-2

Items to check before autotune . . . . . . . . . . . . . . . . . . 5-4

Autotune barrel control applications. . . . . . . . . . . . . . . 5-4

Example: Autotune non–barrel control applications. . . . 5-7

Troubleshooting Autotune . . . . . . . . . . . . . . . . . . . . . . 5-7

Using the Output Image Table. . . . . . . . . . . . . . . . . . . . . . 5-8

Global Commands to All Loops . . . . . . . . . . . . . . . . . . 5-9

BTM Auto Tune . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-10

Chapter 6

Input Image Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Implied Decimal Point . . . . . . . . . . . . . . . . . . . . . . . . . 6-1

Chapter 7

About the Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1

Calibration Codes and Status . . . . . . . . . . . . . . . . . . . . 7-1

Calibration Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . 7-2

Chapter 8

Troubleshooting with LED Indicators. . . . . . . . . . . . . . . . . 8-1

Locating Error Code Information . . . . . . . . . . . . . . . . . . . . 8-2

Chapter 9

Obtaining the Sample Program from the Internet . . . . . . . . 9-1

To Access the Internet:. . . . . . . . . . . . . . . . . . . . . . . . . 9-1

RSLogix500 Version. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1

BTM Firmware Revision . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1

Support for 5/03, 5/04, 5/04P, 5/05, and

5/05P Processors Using BTM201.rss . . . . . . . . . . . . . . . . . . 9-1

BTM201.rss Data Table Layout . . . . . . . . . . . . . . . . . . . 9-2

Download and Upload Settings . . . . . . . . . . . . . . . . . . 9-3

BTM201.rss Programming Notes . . . . . . . . . . . . . . . . . . 9-5

Support for 5/02 Processors Using BTM50220.RSS . . . . . . . 9-7

BTM50220.RSS Data table layout. . . . . . . . . . . . . . . . . . 9-7

Download and Upload Settings . . . . . . . . . . . . . . . . . . 9-7

General Notes for Programming the 1746-BTM. . . . . . . . . . 9-9

Publication 1746-UM010 B- EN-P - April 2001

TOC-4 Table of Contents

Publication 1746-UM010B-EN-P - April 2001

Getting Started

This chapter gives you information on:

• the function of the temperature control module

• features of the temperature control module

• time–proportioned output (TPO)

• module addressing

• response to slot disa bli ng

Chapter

1

Temperature Control Using a BTM Module in an SLC System

ATTENTION

Use the 1746–BTM module only for barrel
temperature control for injection mold ing
applications or extruders in a local I/O chassis. Any
other applications are not supported.

!

The temperature control module is an intelligent I/O module that can
provide a maximum of 4 PID loops for temperature control. The
module has 4 analog thermocouple (TC) inputs. Each analog input
functions as the process variable (PV) for a PID loop. The PID
algorithm and tuning–assisted–process (TAP) algorithm are performed
on the module for each of the loops. The control–variable (CV)
output of each loop, either analog output or time–proportioned
output (TPO), is sent from the module to the SLC data table. Your
application ladder logic must access the CV value in the data table and
send the analog or TPO data to an output module to close the loop.

Figure 1.1

A 1746–BTM module with 4 PID logic channels, showing one complete PID loop

SLC data table

CV

1 Publication 1746-UM010 B- EN-P - April 2001

CV

CV
CV

CV
CV

output module
analog or TPO

loop logic
loop logic
loop logic
loop logic

PV
PV
PV
PV

CV

heater

process to be
controlled

TC

1-2 Getting Started

Features of the T emperature Control Module

The 1746–BTM module provides:

• 4 independent temperature control loops

• autotune PID loops (one loop or any combination of loops can

be autotuned while other loops are running)

• a unique start–up algorithm to minimize overshoot

• an isolated thermocouple (J and K) input for each PID loop

• 16–bit analog–to–digital converter resolution (0.1° resolution)

• a heat CV signal (for each PID loop) as a numeric % value

• a cool CV signal (for each PID loop) as a numeric % value

• a heat CV signal (for each PID loop) as a TPO bit

• a cool CV signal (for each PID loop) as a TPO bit

• temperature values in C ° or F °

• self–calibration (external reference required)

• user–selectable high and low alarms with dead band for

hysteresis

• input open–circuit detection

Module Outputs

The BTM module sends the control variable (CV) for heating an d/or
cooling each loop to the SLC processor’s input image table as both of:

• numeric value (current CV)

• time–proportioned output (TPO)

Current CV

Y our ladder logic should read the numeric value (current CV), scale it,
and send it to an analog output module to generate the control signal
to an analog temperature control actuator. If using the sample
program look for current CVs in N10:208–211 for loops 1–4. Refer
to Sample Program on page 9-1.

TPO

The module returns the heat TPO (bit 6) and cool TPO (bit 7) in input
image table words 8–11 for loops 1–4. The sample program sends
TPO signals to a digital output module to generate the control signal
to a digital temperature control actuator. Refer to Sample Program on
page 9-1.

Publication 1746-UM010B-EN-P - April 2001

Figure 1.2 TPO timing diagram

Getting Started 1-3

TPO bit

BTM

Module

On

Off

Y

X

SLC 5/0x

I/O Image Table

Output Image

Slot e

See Figure 1.3 on

page 1-4

Input Image

Slot e

See Figure 1.3 on

page 1-4

CV% = (40%)

X = on time (2.0 sec)

Y = TPO period (5.00 sec)

data in parenthesis refers to
sample program values.

The TPO duty cycle (Y) must be considerable shorter in time than
the system dead time. For additional information, Refer to Autotune
a Loop on page 5-2.

The following memory map shows you how the SLC processor’s
output and input image tables are defined for the module. See Table

9.A: BTM201.r s s N7 Da t a Table on pag e 9-2.

Bit 15 Bit 0 Address

Loop 1 configuration data word 0 O:e.0

Slot e portion of
SLC image table
for BTM module

output

image

16 words

input

image

16 words

Loop 2 configuration data word 1 O:e.1
Loop 3 configuration data word 2 O:e.2
Loop 4 configuration data word 3 O:e.3
Loop 1 run setpoint value word 4 O:e.4
Loop 2 run setpoint value word 5 O:e.5
Loop 3 run setpoint value word 6 O:e.6
Loop 4 run setpoint value word 7 O:e.7
Loop 1 manual output value word 8 O:e.8
Loop 2 manual output value word 9 O:e.9
Loop 3 manual output value word 10 O:e.10
Loop 4 manual output value word 11 O:e.11
miscellaneous control bits word 12 O:e.12
not used word 13 O:e.13
not used word 14 O:e.14
not used word 15 O:e.15

Loop 1 temper ature word 0 I:e.0
Loop 2 temper ature word 1 I:e.1
Loop 3 temper ature word 2 I:e.2
Loop 4 temper ature word 3 I:e.3
Loop 1 configuration status word 4 I:e.4
Loop 2 configuration status word 5 I:e.5
Loop 3 configuration status word 6 I:e.6
Loop 4 configuration status word 7 I:e.7
Loop 1 control status and TPO word 8 I:e.8
Loop 2 control status and TPO word 9 I:e.9
Loop 3 control status and TPO word 10 I:e.10
Loop 4 control status and TPO word 11 I:e.11
If using the sample program,

variables in words 12-15, including
current CVs, are multiplexed and
scanned into N10:200-243

word 12 I:e.12
word 13 I:e.13
word 14 I:e.14
word 15 I:e.15

Publication 1746-UM010 B- EN-P - April 2001

1-4 Getting Started

Module Addressing

Input Image Table Address Output Image Table Address

slot slot

file type file type

When you enter the module ID in processor configuration (off-line),
the processor automatically reserves the required number of I/O
image table words. In the figure below, that section of the I/O image

table is designated by “slot e”. Its location in the I/O image table is
determined by the module’s slot location “e” in the I/O chassis. Slot
location “e” is a required addressing unit when referring to the
module in ladder logic. For the sample program’s data table layout,
See Table 9.A: BTM201.rss N7 Data Table on page 9-2. See Figure 1.3
for an explanation of the image table addresses

Figure 1.3 .

word

I : e . 6 O : e . 6

element
delimiter

word
delimiter

element
delimiter

word

word
delimiter

Response to Slot Disabling

By writing to the status file in your modular SLC processor you can
disable any chassis slot. See your SLC programming manual for the
slot disable/enable procedure.

ATTENTION

Always understand the implications of disabling the
module before using the slot disable feature.

!

Input response

When the slot for this module is disabled, the module continues to
update its inputs. However, the SLC processor does not read from a
module whose slot is disabled. Therefore, inputs appearing in the
processor image table remain in their last state, and the module’s
updated inputs are not read. When the processor re–enabl es the
module slot, the current state of module inputs are read by the
controller during the subsequent scan.

Output response

Publication 1746-UM010B-EN-P - April 2001

When the slot for this module is disabled, configuration words in the
SLC processor’s output image table are held in their last state and not
transferred to the module. When the slot is re–enabled, output image
table words are transferred to the module during the subsequent scan.

Installing and Wiring

This document gives you information about:

• avoiding electrostatic damage

• compliance with European Union directive

• determining the module’s chassis power requirement

• planning for sufficient enclosure depth

• choosing a module slot in a local I/O chassis

• installing the module

• wiring the module

Chapter

2

Avoiding Electrostatic Damage

Electrostatic discharge can damage semiconductor devices inside this
module if you touch backplane connector pins. Guard against
electrostatic damage by observing the following precautions:

ATTENTION

Electrostatic discharge can degrade performance or
cause permanent damage. Handle the module as
stated below.

!

• Touch a grounded object to rid yourself of charge before

handling.

• Wear an approved wrist strap when handling the module.

• Handle the module from the front, away from the backplane

connector.

• Do not touch backplane connector pins.

1 Publication 1746-UM010 B- EN-P - April 2001

2-2 Installing and Wiring

European Communities (EC) Directive Compliance

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 the Council Directive 89/336/EC
Electromagnetic Compatibility (EMC) by applying the following
standards, in whole or in part, documented in a technical construction
file:

• EN 50081-2 EMC — Generic Emissi on Standard, Part 2 —

Industrial Environment

• EN 5001082-2 EMC — 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/EC 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 Allen-Bradley
publication Industrial Automation Wiring and Grounding Guidelines,
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-UM010B-EN-P - April 2001

Installing and Wiring 2-3

Determining Power Requirements

Choosing a Module Slot in a Local I/O Chassis

When computing power supply requirements, add the values shown
in Table 2.A to the requirements of all other modules in the SLC
chassis to prevent overloading the chassis power supply.

Table 2.A Power Supply Requirements

5V dc amps 24V dc amps

0.110 0.085

Place your module in any slot of an SLC500 module, or modular

expansion chassis, except for the left–most slot (slot 0), reserved for
the SLC processor or adapter modules.

IMPORTANT

For proper operation, use this module with a local
processor. The module is not designed to operate in
a remote chassis.

Installation conside rations

Most thermocouple–type applications require an industrial enclosure
to reduce the effects of electrical interference. Thermocouple inputs
are highly susceptible to electrical noises due to the small signal
amplitudes (microvolt/C °). Isolate them from other input wiring and
modules that radiate electrical interference.

Group your modules within the I/O chassis to minimize adverse
effects from radiated electrical noise and heat. Consider the following
conditions when selecting a slot location. Position the module away
from modules that:

• connect to sources of electrical noise such as relays and ac

motor drives

• generate significant heat, such as 32–point I/O modules

Publication 1746-UM010 B- EN-P - April 2001

2-4 Installing and Wiring

Installing the Module

Follow this procedure:

ATTENTION

Never install, remove, or wire modules with power
applied to the chassis or devices wired to the
module.

!

1. Align the circuit board of the thermocouple module with the

card guides located at the top and bottom of the chassis.

2. Slide the module into the chassis until both top and bottom

retaining clips are secured. Apply firm even pressure on the
module to attach it to its backplane connector. Never force the
module into the slot.

3. Cover unused slots with the card slot filler, catalog number

1746–N2.

4. To remove, press the releases at the top and bottom of the

module, and slide the module out of the chassis slot.

retaining clips

card guides

top and bottom
releases

Publication 1746-UM010B-EN-P - April 2001

Installing and Wiring 2-5

Removing th e terminal block

When installing the module, it is not necessary to remove the terminal
block. But if you need to remove it, follow this procedure:

1. Alternately loosen the two retaining screw s to avoid cracking the

terminal block.

2. Grasp the terminal block at the top and bottom and pull

outward and down. When removing or installing the terminal
block be careful not to damage the CJC sensors.

Tip: The R eplacement Part Number
for the Terminal Block with the CJCs
is 1746-RT32.
You cannot purchase a CJC by itself.

CJC sensors

retaining screws

3. Use the write–on label to identify the module and its location.

SLOT

MODULE

RACK

Publication 1746-UM010 B- EN-P - April 2001

2-6 Installing and Wiring

Wiring the Module

The module has an 18–position, removable terminal block. The
terminal block pin–out is shown below.

ATTENTION

Disconnect power to the SLC before attempting to
install, remove, or wire the removable terminal
wiring block.

!

Figure 2.1 Terminal block pin out.

Retaining Screw

Channel 0+

Channel 0­Channel 1+
Channel 1-

Channel 2+
Channel 2-

Channel 3+

Channel 3-

spare part catalog number:

n/c

1746-RT32

CJC Assembly

Do NOT use these
connections

CJC Assembly

Retaining Screw

CJC A+
CJC A-

CJC B+
CJC B-

Cold Junction Compensation (CJC)

ATTENTION

!

In case of accidental removal of one or both thermistors, replace them
by connecting them across the CJC terminals located at the top and/or
bottom left side of the terminal block. Always connect the red lug to
the (+) terminal (to CJC A+ or CJC B+).

Do not remove or loosen the cold junction
compensating thermistors located on the terminal
block. Both thermistors are critical to ensure

accurate thermocouple input readings at each
channel. The module will not operate in the

thermocouple mode if a thermistor is removed

Publication 1746-UM010B-EN-P - April 2001

Installing and Wiring 2-7

Figure 2.2 Thermistor place me nt on t he bot t om of the terminal block

Always attach red
lug to the CJC+
terminal

Wiring consi derations

Follow the guidelines below when planning your system wiring.

• To limit th e pickup of electrical noise, keep thermocouple and

millivolt signal wires away from power and load lines.

• For high immunity to electrical noise, use Alpha 5121 (shielded,

twisted pair) or equivalent wire for millivolt sensors; or use
shielded, twisted pair thermocouple extension lead wire
specified by the thermocouple manufacturer. Using the incorrect
type of thermocouple extension wire or not following the
correct polarity may cause invalid readings. See IEEE Std. 518,
Section 6.4.2.7 or contact your sensor manufacturer for
additional details.

• When trimming cable leads, minimize the length of unshielded

wires.

• Ground the shield drain wire at only one end of the cable. The

preferred location is at the I/O chassis ground (See Figure 2.4).

• For maximum noise reduction, use 3/8 inch braid wire to

connect cable shields to the nearest I/O chassis mounting bolt.
Then connect the I/O chassis to earth ground (See Figure 2.4).
These connections are a requirement regardless of cable type.

• Tighten terminal scre ws . Ex ce ss i ve ti gh te ni n g c an stri p th e

screw.

• The open–circuit detector generates approximately 20 nano–

amperes into the thermocouple cable. A total lead resistance of
25 ohms (12.5 one–way) will produce 0.5 mV of error.

• Follow system grounding and wiring guidelines found in your

SLC 500 Modular Hardware Installation and Operation Manual,
publication 1747–6.2.

Publication 1746-UM010 B- EN-P - April 2001

2-8 Installing and Wiring

Preparing and Wiring the Cables

To prepare and connect cable leads and drain wires, follow these
steps:

Figure 2.3 Cable lead and drain wire preparation

Remove the foil shield
and drain wire from
sensor-end of the cable

Signal Wires

Extract th e d r ain wire but
remove the foil shield, at
the module-end of the
cable.

Drain Wire

Signal Wires

1. At each end of the cable, s trip s ome casi ng to expo se in divid ual

wires.

2. Trim signal wires to 5–inch lengths beyond the cable casing.

Strip about 3/16 inch (4.76 mm) of insulation to expose the ends
of the wires.

3. At the module–end of the cables:

- extract the drain wire and signal wires

- remove the foil shield

- bundle the input cables with a cable strap

4. Connect drain wires together and solder them to a 3/8” wire

braid, 12” long. Keep drain wires as short as possible.

5. Connect the 3/8” wire braid to the nearest chassis mounting

bolt.

Publication 1746-UM010B-EN-P - April 2001

6. Connect the signal wires of each channel to the terminal block.

Installing and Wiring 2-9

7. At the source-end of cables from mV devices (See Figure 2.3

and Figure 2.4):

• remove the drain wire and foil shield

• apply shrink wrap as an option

• connect to mV devices keeping the leads short

Figure 2.4 Cable Preparation to Minimize Electrical Noise Interference

Wires

3/8”

Make
unshielded
wires as
short as
possible.

Limit braid length to 12” or
less. Solder braid to lug on
bottom row of I/O chassis
bolts.

IMPORTANT

Make unshielded wires
as short as possible.

Solder drain wires to
braid at casing.

Connect I/O

chassis bolt to

earth ground

3/8”

Signal
Wires

Cables

Terminal
Block

Chnl 0

Chnl 1

Chnl 2

Chnl 3

n/c

If noise persists, try grounding the opposite end of
the cable. Ground one end only.

Publication 1746-UM010 B- EN-P - April 2001

2-10 Installing and Wiring

Specifications

Backplane Current
consumption

110 mA at 5V dc
85 mA at 24V dc

Backplane power consumption 0.6W maximum (0.55W @ 5V dc, 2W @ 24V dc)
Number of channels 4 (backplane and channel-to-channel isolated)
I/O chassis location any I/O module slot except 0
A/D conversion method sigma-delta modulation
Input filtering analog filter with low pass digital filter
Normal mode rejection

between [+]input and [-]input
Common mode rejection

between inputs and chassis

greater than 50 dB at 50 Hz
greater than 60 dB at 60 Hz

greater than 120 dB at 50/60 Hz with 1K ohm
imbalance

ground
Channel bandwidth (-3db) 8 Hz
Calibration once every six months
Isolation 1000V transient or 150 VAC continuous

channel-to-channel or channel-to-backplane

Agency
Certifications

When product or
packaging is
marked:

Listed Industrial Control Equipment

Certified Process Control Equipment
Certified for use in Class I, Division 2, Groups A, B, C, D or
nonhazardous locations

Marked for all applicable directives
Marked for all applicable acts

N223

Publication 1746-UM010B-EN-P - April 2001