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
, 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
, 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+