lefthandedsquirrel
Member
Hey guys, this is my first post here but I've gotten some answers from other posts already.
Here's my problem:
I have several machines using ALL Siemens PLCs, but I have very limited Siemens experience. Over the last several months, I've replaced about a dozen analog input modules (6ES7 331-7PF01-0AB0) for what appears to be the same reason. I'm getting the red light "SF" and my HMI shows no input signal. If I replace the card, the fault goes away so I know it's not a sensor issue. It has happened twice now during a power blink but several times with no cause that I can see. The problem is on the same type of module but in several different panels on at least three different machines. There's not a grounding issue that I can see.
Design flaw?
Dirty power?
Gremlins?
Any suggestions?
Here's my problem:
I have several machines using ALL Siemens PLCs, but I have very limited Siemens experience. Over the last several months, I've replaced about a dozen analog input modules (6ES7 331-7PF01-0AB0) for what appears to be the same reason. I'm getting the red light "SF" and my HMI shows no input signal. If I replace the card, the fault goes away so I know it's not a sensor issue. It has happened twice now during a power blink but several times with no cause that I can see. The problem is on the same type of module but in several different panels on at least three different machines. There's not a grounding issue that I can see.
Design flaw?
Dirty power?
Gremlins?
Any suggestions?