We are experiencing a strange failure in FLEX I/O Non-Isolated Thermocouple/RTD/mV modules 1974-IRT8/B. these modules have a communication with Control logix 5561 PLC by means of ControlNet adapter module ( 1794-ACNR15 ). we checked the RTD wires and power many times before replacing the modules but without success.

The failed module have a green power led on indication and with a permanent red led on channel 0.

Anyone know what the cause of module failure could be? has anyone experienced this before?

 

Have you set the run bit for the DeviceNet scanner? Local:X:O.CommandRegister.Run

Regards

 

> Have you set the run bit for the DeviceNet scanner?
> Local:X:O.CommandRegister.Run

Thank you for the reply,
the run bit do the job even in ControlNet communications? because I didn't specify that we don't have DeviceNet, I'll post feedback later ..

 

Ok, I can confirm that this bit "Local:X:O.CommandRegister.Run" doesn't exist in controller tag, but I heard that AB IRT modules manufactured between January 1, 2010 and May 31, 2010 has a potential anomaly, can anyone confirm this?