Rockwell Automation Allen-Bradley B Series User manual

Publication 1746-IN010D-EN-P - June 2004
Installation Instructions
SLC™ 500 4-Channel Thermocouple/mV Input
Module
(Catalog Number 1746-NT4, Series B)
Inside…............................................................................................Page
For More Information............................................................................... 3
Hazardous Location Considerations .........................................................4
Environnements dangereux ..................................................................... 4
Overview ...................................................................................................5
Required Tools and Equipment ................................................................ 6
Electrostatic Damage............................................................................... 7
NT4 Power Requirements........................................................................ 7
Modular Chassis Considerations............................................................. 7
Fixed Expansion Chassis Considerations................................................. 8
General Considerations ........................................................................... 8
Terminal Block Removal........................................................................... 8
Module Installation and Removal.......................................................... 10
Terminal Wiring...................................................................................... 11
Thermocouple Junctions........................................................................ 12
Wiring Considerations ........................................................................... 13
Wiring Input Devices to the NT4 ........................................................... 15
Cold-Junction Compensation (CJC) ....................................................... 16
Module Addressing................................................................................ 17
Channel Configuration ........................................................................... 17
Specifications ........................................................................................ 19

2SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
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://www.ab.com/manuals/gi) 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 we use notes to make you aware of safety considerations.
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
•recognize the consequence
SHOCK HAZARD Labels may be located on or inside the drive to alert people that dangerous voltage may
be present.
BURN HAZARD Labels may be located on or inside the drive to alert people that surfaces may be
dangerous temperatures.

SLC™ 500 4-Channel Thermocouple/mV Input Module 3
Publication 1746-IN010D-EN-P - June 2004
For More Information
Related Publications
If you would like a manual, you can:
•download an electronic version from the internet:
www.theautomationbookstore.com
•order a printed manual by:
–contacting your local distributor or Rockwell Automation representative
–visiting www.theautomationbookstore.com
–calling 1.800.963.9548 (USA/Canada) or 001.330.725.1574 (Outside
USA/Canada)
For: Refer to this Document: Pub. No.
A more detailed description on how to install and
use your SLC 500 4-Channel Thermocouple/mV Input
Module.
Thermocouple/mV Input Module
User Manual
1746-6.6.1
A more detailed description on how to install and
use your SLC 500 Modular Hardware Style Control
System.
SLC™ 500 Modular Hardware
Style User Manual
1747-UM011
A more detailed description on how to install and
use your SLC 500 Fixed Hardware Style Control
System.
SLC™ 500 Fixed Hardware Style
Installation and Operation Manual
1747-6.21

4SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
Hazardous Location Considerations
This equipment is suitable for use in Class I, Division 2, Groups A, B, C, D or
non-hazardous locations only. The following WARNING statement applies to use in
hazardous locations.
Environnements dangereux
Cet équipement est conçu pour être utilisé dans des environnements de Classe I,
Division 2, Groupes A, B, C, D ou non dangereux. La mise en garde suivante
s’applique à une utilisation dans des environnements dangereux.
WARNING EXPLOSION HAZARD
•Substitution of components may impair suitability for Class
I, Division 2.
•Do not replace components or disconnect equipment
unless power has been switched off or the area is known to
be non-hazardous.
•Do not connect or disconnect components unless power
has been switched off or the area is known to be
non-hazardous.
•All wiring must comply with N.E.C. article 501-4(b).
WARNING DANGER D’EXPLOSION
•La substitution de composants peut rendre cet équipement
impropre à une utilisation en environnement de Classe I,
Division 2.
•Ne pas remplacer de composants ou déconnecter
l'équipement sans s'être assuré que l'alimentation est
coupée.
•Ne pas connecter ou déconnecter des composants sans
s'être assuré que l'alimentation est coupée.

SLC™ 500 4-Channel Thermocouple/mV Input Module 5
Publication 1746-IN010D-EN-P - June 2004
Overview
The thermocouple/mV input module receives and stores digitally converted
thermocouple and/or millivolt (mV) analog data into 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 or mV analog sensors. See the input
specifications beginning on page 21 for thermocouple types, their associated
temperature ranges, and the analog input signal ranges that each 1747-NT4 channel
will support. Each input channel is individually configurable via software for a
specific input device and provides open-circuit, over-range, and under-range
detection and indication.
The module contains a removable terminal block with two cold-junction
compensation (CJC) sensors. There are no output channels on the module.
Configuration is done via the user program. There are no DIP switches.
Channel Status LEDs
Channel status LEDs indicate the status for channels 0 through 3. Related error
information is contained in the channel status word. This includes conditions such
as:
•normal operation
•channel-related configuration errors
•open-circuit errors
•out-of-range errors
All channel errors are recoverable errors.
Module Status LED
The module status LED shows diagnostic or operating errors related to the module.
These non-recoverable errors may be detected during power-up or during
operation. Once an error has been detected, the module no longer communicates
with the SLC processor. Channel states are disabled, and data words are cleared (0).
Failure of any diagnostic test results in a non-recoverable error and requires the
assistance of your local Allen-Bradley distributor or Rockwell Automation
representative.

6SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
1747-NT4 Thermocouple Module Hardware Features
Required Tools and Equipment
Have the following tools and equipment ready:
•medium blade screwdriver
•medium cross-head screwdriver
•thermocouple or millivolt sensor
•appropriate thermocouple extension wire (if needed)
•thermocouple/mV input module (1746-NT4)
•programming equipment
INPUT
CJC A+
SHIELD
SHIELD
SHIELD
SHIELD
CHL3-
CHL3+
CHL2-
CHL2+
CHL1-
CHL1+
CHL0-
CHL0+
Do Not
Remove
CJC A±
Do Not
Remove
CJC B±
Do Not
Remove
CJC B+
Do Not
Remove
SHIELD
ANLG
MODULE STATUS
0
1
2
3
CHANNEL
STATUS
THERMOCOUPLE/mV
COM
Door Label
Channel Status
LEDs (Green)
Module Status
LED (Green)
Removable
Terminal Block
CJC Sensors
Cable Tie Slots

SLC™ 500 4-Channel Thermocouple/mV Input Module 7
Publication 1746-IN010D-EN-P - June 2004
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.
•Wear an approved wrist strap grounding device when handling the module.
•Touch a grounded object to rid yourself of electrostatic charge before
handling the module.
•Handle the module from the front, away from the backplane connector. Do
not touch backplane connector pins.
•Keep the module in its static-shield bag when not in use, or during
shipment.
NT4 Power Requirements
The thermocouple module receives its power through the SLC 500 chassis
backplane from the fixed or modular +5V dc/+24V dc chassis power supply. The
maximum current drawn by the module is shown in the table below.
When you are using a modular system configuration, add the values shown in the
table above to the requirements of all other modules in the SLC chassis to prevent
overloading the chassis power supply.
When you are using a fixed system controller, refer to the important note on page 8
about module compatibility in a 2-slot fixed expansion chassis.
Modular Chassis Considerations
Place your thermocouple module in any slot of an SLC 500 modular, or modular
expansion chassis, except for the extreme left slot (slot 0) in the first chassis. This
slot is reserved for the processor or adapter modules.
ATTENTION Electrostatic discharge can degrade performance or cause
permanent damage. Handle the module as stated below.
5V dc Amps 24V dc Amps
0.060 0.040

8SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
Fixed Expansion Chassis Considerations
General Considerations
Most applications require installation in an industrial enclosure to reduce the effects
of electrical interference. Thermocouple inputs are highly susceptible to electrical
noises due to the small amplitudes of their signal (microvolt/°C).
Group your modules to minimize adverse effects from radiated electrical noise and
heat. Consider the following conditions when selecting a slot for the thermocouple
module. Position the module:
•in a slot away from sources of electrical noise, such as hard-contact switches,
relays, and AC motor drives
•away from modules which generate significant radiated heat, such as
32-point I/O modules
In addition, route shielded, twisted-pair thermocouple or millivolt input wiring
away from any high-voltage I/O wiring.
Terminal Block Removal
When installing the module in a chassis, it is not necessary to remove the terminal
block from the module. However, if the terminal block is removed, use the write-on
label located on the side of the terminal block to identify the module location and
type.
IMPORTANT The 2-slot, SLC 500 fixed I/O expansion chassis (1746-A2) will
support only specific combinations of modules. If you are using
the thermocouple module in a 2-slot expansion chassis with
another SLC I/O or communication module, refer to the
SLC 500™Thermocouple/mV Input Module User Manual,
1746-6.6.1
ATTENTION Disconnect power to the SLC before attempting to install,
remove, or wire the removable terminal wiring block.
To avoid cracking the removable terminal block, alternate the
removal of the slotted terminal block release screws.

SLC™ 500 4-Channel Thermocouple/mV Input Module 9
Publication 1746-IN010D-EN-P - June 2004
To remove the terminal block:
1. Loosen the two terminal block release screws.
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.
CJC Sensors
Terminal Block Release Screws
Max. Torque = 0.7 to 0.9 Nm (6 to 8
in-lb)

10 SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
Module Installation and Removal
Module Installation Procedure
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 all unused slots with the Card Slot Filler, Catalog Number 1746-N2.
Module Removal Procedure
1. Press the releases at the top and bottom of the module and slide the module
out of the chassis slot.
2. Cover all unused slots with the Card Slot Filler, Catalog Number 1746-N2.
Top and Bottom Module
Card
Guide