Troubleshooting the 18 KVA UPS

One of our clients has or rather had, a BEST FERUPS 18 KVA UPS. It has stopped working and I was given the following report:

Radio guy: The power went out, the generator started, then I heard a bang.

Myself: You heard a bang?

RG: Yeah, a big BANG!

Myself: You heard a big bang.

And so he did:

Best FERUPS 18 KVA control board.
Best FERUPS 18 KVA control board.
Best FE18KVA control board, MOV destruction
Best FE18KVA control board, MOV destruction

The primary damage is around two MOV’s mounted on the other side of the board. This is the power sense (voltage sample) input to the board. We have attempted to repair it, but alas, it is not repairable. A replacement board runs over $1,400.00 from Eaton Powerware. Since this unit also needs a new set of batteries, it is likely best to replace the entire unit.