Major fault S3

A.B. PLC Micrologix1500 "major fault"

The fault was saying that the card was a miss match and I never changed it. I decided to change the input card # 3 and I hit "clear major fault" and it worked for me. Do you think I did the correct thing or I was lucky the plc recovered by its self?

Most likely, yes. If you tried to clear the fault first, and it did not clear, then the card was probably faulty and the CPU was unable to identify it.

It is also possible that the card connection could have been interrupted, needing to be reseated. So, you might give it one more chance (power down, install it, power up) before declaring it fubar.

Paul

Thanks Paul I'll post results