Rockwell Automation 1746-INT4 Thermocouple/MV Isolated/ User Manual - Manual (Page 12)

Publication 1746-UM614B-EN-P - September 2007
12 Module Overview
Diagnostic LED Indicator
The module contains diagnostic LED indicator that help you identify
the source of problems that may occur when cycling power or during
normal operation.
Power cycling and channel diagnostics are explained in Chapter 8,
Module Diagnostics and Troubleshooting.
System Overview The module communicates with the SLC 500 processor and receives
+5V dc and +24V dc power from the system power supply through
the parallel backplane interface. No external power supply is
required. You may install as many thermocouple modules in the
system as the power supply can support.
Module Placement
Each module channel can receive input signals from a thermocouple
or a millivolt analog input device. You configure each channel to
accept either one. When configured for thermocouple input types, the
module converts analog input voltages into cold-junction
compensated and linearized, digital temperature readings. The
module uses the National Bureau of Standards (NBS) Monograph 125
and 161 based on IPTS-68 for thermocouple linearization.
When configured for millivolt analog inputs, the module converts
analog values directly into digital counts. The module assumes that
the mV input signal is linear.
SLC Processor Thermocouple Modules