PowerFlex 753 ground fault issue

[Ken Moore]

Well...
After replacing the line reactor, we placed the pump in service and it has been running for about 25 hours without issue.

Learn something new everyday.

 

[Bit_Bucket_07]

Well...
After replacing the line reactor, we placed the pump in service and it has been running for about 25 hours without issue.

Learn something new everyday.

Interesting.

The line reactor showed no ground faults when tested?

 

[jraef]

Well...
After replacing the line reactor, we placed the pump in service and it has been running for about 25 hours without issue.

Learn something new everyday.

Makes no sense. The GF detection for a PF750 drive is based on the OUTUT current sensors doing a residual current detection method between them, resulting in a 25% difference, it's not like a GFCI type circuit. Something on the input side would not be seen by that at all. I'm assuming here that you got an F13 fault, right?

I'm more inclined to believe that there was some sort of internal moisture or condensation in the drive, and in having it unpowered for as long as it took to replace the reactor, it dried out.

 

[alive15]

But he had already changed the drive before and still had the same ground fault issue, correct? Unless your new drive captured the same moisture in the same spot inside your drive causing the ground fault. Did you try adding an air line into your cabinet with about 5 PSI, so as not to let any moisture get into your cabinet?

 

[Ken Moore]

I agree it makes no sense, the drives are in MCC sections in an environmentally controlled building. Yes the drive was swapped once, the motor twice.