Rockwell Automation 1746-INT4 Thermocouple/MV Isolated/ User Manual - Manual (Page 63)

Publication 1746-UM614B-EN-P - September 2007
Ladder Programming Examples 63
Monitor Channel Status
Bits This example shows how you could monitor the open-circuit error bit
of each channel and set an alarm bit if the module detects an open
input. An open-circuit error can occur if a thermocouple or CJC
thermistor wire breaks or becomes disconnected from the terminal
block.
In this example, we monitor the channel enable bit (bit 11) and the
open-input bit (bit 12) in channel status words I:3.4 through I:3.7, and
use output image bits O:2.0/0…3 as alarm bits.
IMPORTANT
If a CJC thermistor is not installed or is damaged, all four
alarms are set, and all four channel LEDs blink.