Grounding guidelines – Rockwell Automation 1769-IT6 Compact I/O 1769-IT6 Thermocouple/mV Input Module User Manual

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Rockwell Automation Publication 1769-UM004B-EN-P - March 2010

Chapter 2 Quick Start for Experienced Users

• To be sure of optimum accuracy, limit overall cable impedance by keeping a

cable as short as possible. Locate the module as close to input devices as the
application permits.

Grounding Guidelines

• This product is intended to be mounted to a well-grounded mounting

surface such as a metal panel. Additional grounding connections from the
module’s mounting tabs or DIN rail (if used) are not required unless the
mounting surface cannot be grounded.

• Keep cable shield connections to ground as short as possible.
• Ground the shield drain wire at one end only. The preferred location is as

follows.

For grounded thermocouples or millivolt sensors, this is at the sensor
end.

For insulated/ungrounded thermocouples, this is at the module end.
Contact your sensor manufacturer for additional details.

• Refer to Industrial Automation Wiring and Grounding Guidelines,

Allen-Bradley publication

1770-4.1

, for additional information.

Figure 2 - Terminal Connections with CJC Sensors

ATTENTION: The possibility exists that a grounded or exposed
thermocouple can become shorted to a potential greater than that of the
thermocouple itself. Due to possible shock hazard, take care when wiring
grounded or exposed thermocouples. See

Appendix D

, Using

Thermocouple Junctions.

NC

IN 0+

IN 0-

IN 3+

IN 1 +

IN 3-

IN 1-

IN 4+

IN 2+

IN 4-

IN 2-

IN 5+

IN 5-

NC

CJC 0+

CJC 0-

CJC 1-

CJC 1+

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