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

SLC™ 500 4-Channel Thermocouple/mV Input Module 11
Publication 1746-IN010D-EN-P - June 2004
Terminal Wiring
The thermocouple module contains a green, 18-position, removable terminal block.
The terminal pin-out is shown below.
Terminal screws accept a maximum of two #14 AWG (2 mm2) wires. Tighten
terminal screws only tight enough to immobilize wires. Maximum torque on
terminal screws is 0.7 to 0.9 Nm (6 to 8 in-lbs).
ATTENTION Disconnect power to the SLC before attempting to install,
remove, or wire the removable terminal wiring block.
(Terminal Block Spare Part Catalog Number 1746-RT32)
CJC A+
CJC A-
CJC Assembly
Shield
Shield
Shield
Shield
Shield
CJC B+
CJC B-
CJC Assembly
Release Screw Max. Torque =
0.7 to 0.9 Nm (6 to 8 in-lb)
Release Screw Max. Torque =
0.7 to 0.9 Nm (6 to 8 in-lb)
Channel 0+
Channel 0-
Channel 1+
Channel 1-
Channel 2+
Channel 2-
Channel 3+
Channel 3-
Analog Common
[see (1) below]
(1) Replacing a Series A thermocouple module with a Series B module requires that the bottom right terminal (which was
SHIELD on Series A modules) no longer be connected to CHASSIS GROUND if it was previously. Use one of the other
SHIELD terminals.

12 SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
Thermocouple Junctions
There are three types of thermocouple junctions:
•Grounded Junction - The measuring junction is physically connected to the
protective metal sheath providing electrical continuity between junction and
sheath.
•Ungrounded Junction - The measuring junction is electrically isolated from
the protective metal sheath. (Also called Insulated Junction.)
•Exposed Junction - Does not have a protective metal sheath so the
measuring junction is exposed.
The illustration that follows shows each of the three thermocouple types.
Extension Wire Metal Sheath Measuring Junction is connected to sheath.
Measuring Junction is isolated from sheath.
Measuring Junction has no sheath.
Grounded Junction
Ungrounded (Insulated)
Junction
Exposed Junction

SLC™ 500 4-Channel Thermocouple/mV Input Module 13
Publication 1746-IN010D-EN-P - June 2004
Wiring Considerations
Follow the guidelines below when planning your system wiring.
•To limit noise, keep thermocouple and millivolt signal wires as far away as
possible from power and load lines.
•To ensure proper operation and high immunity to electrical noise, always
use Belden™ 8761 (shielded, twisted-pair) or equivalent wire for millivolt
sensors or shielded, twisted-pair thermocouple extension lead wire specified
by the thermocouple manufacturer for the thermocouple type you are using.
Using the incorrect thermocouple extension wire type or not following the
correct polarity convention will cause invalid readings.
•Special considerations for using the analog common (ANALOG COM)
terminal based on thermocouple type:
(See page 12 for an explanation of thermocouple junctions.)
–When using grounded thermocouple(s), jumper the ANALOG COM
terminal to any single active grounded channel’s plus (+) or minus (-)
terminal.
–When using exposed thermocouple(s) that have the thermocouple
junction touching an electrically conductive material, jumper the
ANALOG COM terminal to any single active exposed channel’s plus (+)
or minus (-) terminal.
–When using ungrounded (shielded) or exposed thermocouples that are
not touching an electrically conductive material, do not use the
ANALOG COM terminal.
–When using a mix of grounded, ungrounded, and exposed
thermocouples, jumper the ANALOG COM terminal to any single active
grounded channel’s plus (+) or minus (-) terminal.
ATTENTION The possibility exists that grounded or exposed thermocouples
can become shorted to a potential greater than that of the
thermocouple itself. Due to possible shock hazard, care should
be taken when wiring these types of thermocouples. See
page 12 for definitions of thermocouple junctions.

14 SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
–If millivolt inputs are used, the terminal should be biased to a level
within 2V of the signal of interest. Use 10KΩresistors to create a resistive
voltage divider as shown in the following circuit diagram.
•Ground the shield drain wire at one end only. The preferred location is to
the same point as the sensor ground reference.
–For grounded thermocouples or mV sensors, this is at the sensor.
–For insulated/ungrounded thermocouples, this is at the module.
–Refer to IEEE Std. 518, Section 6.4.2.7 or contact your sensor
manufacturer for additional details.
•If it is necessary to connect the shield at the module, each input channel has
a convenient shield connection screw terminal that provides a connection to
chassis ground. All shields are internally connected, so any shield terminal
can be used with channels 0-3. For maximum noise reduction, one shield
terminal must be connected to earth ground potential, i.e. mounting bolt on
1746 chassis.
TIP The Series A 1746-NT4 does not have an ANALOG COM
terminal and cannot be used with multiple grounded and/or
exposed thermocouples that touch electrically conductive
material. The Series A can be used with a single grounded
and/or exposed thermocouple that touches electrically
conductive material, or multiple grounded thermocouples that
have the protective sheath made of an electrically
non-conductive material such as ceramic.
+
-
+
Strain Gauge
Bridge
NT4
Vcc
10K Ω
10K Ω
variable
fixed
fixed
fixed
Input
(CHL 0, CHL 1, CHL
2, CHL 3)
Analog Com

SLC™ 500 4-Channel Thermocouple/mV Input Module 15
Publication 1746-IN010D-EN-P - June 2004
•Tighten terminal screws using a flat or cross-head screwdriver. Each screw
should be turned tight enough to immobilize the wire’s end. Excessive
tightening can strip the terminal screw. The torque applied to each screw
should not exceed 6 - 8 in-lbs (0.7 - 0.9 Nm) for each terminal.
•The open thermocouple detection circuit injects approximately
12 nanoAmperes into the thermocouple cable. A total lead resistance of
25 Ω(12.5 one-way) will produce 0.3 mV of error. To reduce error, use large
gauge wire with less resistance for long wire runs.
•Follow system grounding and wiring guidelines found in your SLC 500
Installation and Operation Manual, publication number 1747-6.21 (Fixed
Hardware Style) or 1747-UM011 (Modular Hardware Style).
Wiring Input Devices to the NT4
After the thermocouple module is properly installed in the chassis, follow the
wiring procedure below using the proper thermocouple extension cable, or
Belden 8761 for non-thermocouple applications.
To wire your NT4 module, follow these steps.
1. At each end of the cable, strip some casing to expose the individual wires.
2. Trim the signal wires to 2-inch lengths. Strip about 4.76 mm (3/16 inch) of
insulation away to expose the end of the wire.
3. At one end of the cable, twist the drain wire and foil shield together, bend
them away from the cable, and apply shrink wrap. Then earth ground at the
preferred location based on the type of sensor you are using (see wiring
guidelines on page 13).
Cable
Signal Wire
Signal Wire
Signal Wire
Signal Wire
Drain Wire Foil Shield
(Twist together, shrink wrap, and
connect to earth ground.)
(Cut foil shield and
drain wire; then
insulate at cable
end.)

16 SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
4. At the other end of the cable, cut the drain wire and foil shield back to the
cable and apply shrink wrap.
5. Connect the signal wires to the NT4 terminal block and the input.
6. Repeat steps 1 through 5 for each channel on the NT4 module.
Cold-Junction Compensation (CJC)
To obtain accurate readings from each of the channels, the cold-junction
temperature (temperature at the module’s terminal junction between the
thermocouple wire and the input channel) must be compensated for. Two cold-
junction compensating thermistors have been integrated in the removable terminal
block; they must remain installed to retain accuracy.
In case of accidental removal of either or both of the thermistor assemblies, make
sure to replace them by connecting each one across the CJC terminals located at the
top and bottom left side of the terminal block. When connecting the thermistor
assembly at the top of the terminal block (between terminals CJC A+ and CJC A-),
the lug containing the thermistor (marked with red epoxy) should attach to the
uppermost screw terminal (CJC A+). When connecting the thermistor assembly at
the bottom of the terminal block (between terminals CJC B+ and CJC B-), the lug
containing the thermistor should attach to the lowermost screw terminal (CJC B+).
ATTENTION Do not remove or loosen the cold junction compensating
thermistor assemblies located between the two upper and
lower CJC terminals on the terminal block. Both thermistor
assemblies are critical to ensure accurate thermocouple input
readings at each channel. The module will not operate in the
thermocouple mode if either assembly is removed.
CJC
Assembly
Thermistor
(Always attach red lug to
the CJC+ terminal.)
Bottom of Terminal Block

SLC™ 500 4-Channel Thermocouple/mV Input Module 17
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Module Addressing
The following memory map shows you how the output and input image tables are
defined for the thermocouple module.
Channel Configuration
Once the module is installed, each channel on the module can be configured to
establish the way the channel will operate. You configure the channel by entering
bit values into the configuration word using your programming software. Channels
0 through 3 on the NT4 are configured by entering bit values into output words 0
through 3 respectively. Output words 4 through 7 are not used. See the table on
page 18 for bit settings.
SLC 5/0X
Data Files
Slot e
Output Image
Slot e
Input Image
Output
Scan
Input
Scan
Thermocouple
Module Image
Output Image
8 Words
Input Image
8 Words
Output
Image
Input
Image
(Class 1)
Channel 0 Configuration Word
Channel 1 Configuration Word
Channel 2 Configuration Word
Channel 3 Configuration Word
Words 4-7
(not defined)
Channel 0 Data Word
Channel 1 Data Word
Channel 2 Data Word
Channel 3 Data Word
Channel 0 Status Word
Channel 1 Status Word
Channel 2 Status Word
Channel 3 status Word
Address
Bit 15 Bit 0
Address
Bit 15 Bit 0
Word 0
Word 1
Word 2
Word 3
O:e.0
O:e.1
O:e.2
O:e.3
Word 0
Word 1
Word 2
Word 3
Word 4
Word 5
Word 6
Word 7
I:e.0
I:e.1
I:e.2
I:e.3
I:e.4
I:e.5
I:e.6
I:e.7

18 SLC™ 500 4-Channel Thermocouple/mV Input Module
Publication 1746-IN010D-EN-P - June 2004
Channel Configuration Word - Bit Definitions
Define To Select Make these bit settings in the Channel Configuration Word(1)
(1) Bit settings other than those shown in the table are invalid.
15–12(2)
(2) Ensure unused bits 12-15 are always set to zeros.
11109876543210
Input type Thermocouple Type J
Not Used
0000
Thermocouple Type K 0001
Thermocouple Type T 0010
Thermocouple Type E 0011
Thermocouple Type R 0100
Thermocouple Type S 0101
Thermocouple Type B 0110
Thermocouple Type N 0111
±50mV 1000
±100mV 1001
CJC temperature 1111
Data format Engineering units 1(3)
(3) For engineering units x 1, values are expressed in 0.1 degrees or 0.01 mV.
00
Engineering units 10(4)
(4) For engineering units x 10, values are expressed in 1.0 degrees or 0.1 mV.
01
Scaled-for-PID 10
Proportional Counts 11
Open circuit Zero 00
Upscale 01
Downscale 10
Temperature
units
Degrees C(5)
(5) When millivolt input type is selected, the bit setting for temperature units is ignored.
0
Degrees F(5) 1
Channel
filter
frequency
10 Hz 00
50 Hz 01
60 Hz 10
250 Hz 11
Channel
enable
Channel Disabled 0
Channel Enabled 1

SLC™ 500 4-Channel Thermocouple/mV Input Module 19
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Specifications
Electrical Specifications
Backplane Current Consumption 60 mA at 5V dc
40 mA at 24V dc
Backplane Power Consumption 1.3W maximum (0.3W at 5V dc, 1.0W at 24V dc)
Number of Channels 4 (backplane isolated)
I/O Chassis Location Any I/O module slot except slot 0
A/D Conversion Method Sigma-Delta Modulation
Input Filtering Low pass digital filter with programmable notch (filter) frequencies
Normal Mode Rejection (between
[+] input and [-] input)
Greater than 100 dB at 50 Hz (10 Hz, 50 Hz filter frequencies)
Greater than 100 dB at 60 Hz (10 Hz, 60 Hz filter frequencies)
Common Mode Rejection
(between inputs and chassis
ground)
Greater than 150 dB at 50 Hz (10 Hz, 50 Hz filter frequencies)
Greater than 150 dB at 60 Hz (10 Hz, 60 Hz filter frequencies)
Input Filter Cut-Off Frequencies 2.62 Hz at 10 Hz filter frequency
13.1 Hz at 50 Hz filter frequency
15.72 Hz at 60 Hz filter frequency
65.5 Hz at 250 Hz filter frequency
Calibration Module autocalibrates at powerup and whenever a channel is enabled.
Isolation 500V dc one minute between inputs and chassis ground, and between
inputs and backplane.
Maximum Channel-to-Channel
Common-Mode Separation
Series B or later: 2V maximum between any two channels
Series A: 0V separation

20 SLC™ 500 4-Channel Thermocouple/mV Input Module
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Physical Specifications
Environmental Specifications
LED Indicators 5 green status indicators, one for each of 4 channels and one for module
status
Module ID Code 3510
Recommended Cable:
for thermocouple inputs Appropriate shielded, twisted-pair thermocouple extension wire(1)
(1) Refer to the thermocouple manufacturer for the correct extension wire.
for mV inputs Belden #8761 or equivalent
Maximum Wire Size Two 14 AWG wires per terminal
Maximum Cable Impedance 25 ohms maximum loop impedance, for <1LSB error
Removable Terminal Strip Allen-Bradley spare part Catalog Number 1746-RT32
Operating Temperature 0°C to +60°C (+32°F to +140°F)(1)
(1) When the NT4 module detects zero degrees (+/- 3°) at the CJC, it will detect an out of range condition and set values to
downscale -270°C (-454°F). It is recommended that ambient temperature surrounding the SLC 500 system be maintained
above 3°C (37.4°F) in order for the NT4 module to measure temperature correctly without detecting an out of range
condition.
Storage Temperature -40°C to +85°C (-40°F to +185°F)
Relative Humidity 5% to 95% (without condensation)
Certification UL listed
CSA approved
Class I, Division 2, Groups A, B, C, D
CE compliant for all applicable directives when product or packaging is marked