Rockwell Automation T3431-CA ICS Regent Thermo Couple Input Assembly - Manual (Page 15)

Thermocouple Input Assembly (T3431)
P D - 6 0 2 4 M a r - 0 6
15
block areas. Install the thermocouple terminations cover
provided with the termination panel. Allow at least four
hours for temperature stabilization after any significant
temperature change.
2. If possible, terminate unused input channels with the
same thermocouple signal as the next channel, or short the
terminals of the unused input. This will minimize the
pulling affect of a preceding input.
3. Minimize the resistance of the thermocouple extension
wire by using heavier wire gauges.
Radiated Field Susceptibility
Transmitting equipment should not be operated within the
vicinity of the termination panel. Power levels greater than
one watt at a distance of one foot may degrade thermocouple
measurements and eventually cause a permanent fault to be
logged, resulting in a shutdown (clear to 0) of all inputs on the
affected panel.
Grounding
The termination panel should be connected to the system’s
safety or system ground. Use a minimum of #18 stranded
wire. A chassis ground terminal is provided for this purpose.
It is located underneath the wire cover near thermocouple
input 24.
Additional ground terminals are provided at either end of
each terminal block group. These terminals are electrically
connected to the chassis and can be used for thermocouple
shield terminations.
Installing the Termination Panel
The thermocouple termination panel can be mounted in a 19-
inch rack or flush mounted to a panel. Refer to Figure 8 for
overall mounting dimensions for the termination panel and
Mux.