Channel diagnostics, Channel diagnostics -2 – Rockwell Automation 1746-NT4 Series B,D17466.6.1 SLC 500 4-Channel Thermocouple/mV Input Module User Manual User Manual
Page 80
Publication 1746-UM007C-EN-P - July 2004
7-2 Module Diagnostics and Troubleshooting
Channel Diagnostics
When a channel is enabled (bit 11 = 1), a diagnostic check is
performed to see that the channel has been properly configured. In
addition the channel is tested for out-of-range and open-circuit faults
on every scan. If the channel is configured for thermocouple input or
CJC input, the CJC sensors are also checked for out-of-range and open
circuits.
A failure of any channel diagnostic test causes the faulted channel
status LED to blink. All channel faults are indicated in bits 12-15 of the
channel’s status word. Channel faults are self-clearing, and the
channel LED will stop blinking and resume steady illumination when
the fault conditions are corrected.
IMPORTANT
If you clear (0) a channel enable bit (11) all channel
status information is reset.