ControlLogix 1756-PA75 Problems

[ChaseV]

I was wondering if anyone else has had issues with the PA75 bricking on power ups. We had 2 that were a year old brick on us. 1 bricked when the main breaker tripped and the UPS was down for maintenance and on power up it never came back. Now yesterday we power cycled the PA75 from the toggle power switch on it and it also never came back.

Any idea what would be causing this?

 

[A_G]

I was wondering if anyone else has had issues with the PA75 bricking on power ups. We had 2 that were a year old brick on us. 1 bricked when the main breaker tripped and the UPS was down for maintenance and on power up it never came back. Now yesterday we power cycled the PA75 from the toggle power switch on it and it also never came back.

Any idea what would be causing this?

My guess, the first situation may be caused if the 1756-PA75 is not protected with correctly sized fuse/breaker. However the second situation, where you toggled its own power switch, makes me think there is something wrong with this batch of PA75's. Can you check the serial number/date manufactured/revision etc on all these PA75. If they were all made around the same time, could be a bad lot? I would reach out to Rockwell