Recently one of my re-sellers had to rush to site with a replacement module for a PP8FR that had a “faulty” output. Fuse one would blow every time power was applied to the board.
On inspection I removed the main output terminal plug and found a single strand off copper shorting the output. I brushed it off and the unit worked like new.
It is sometimes easier to terminate to the main output plug while removed from the PP8FR. In this case while striping/cutting the cables the tech had inadvertently dropped strands of copper onto the board and one got stuck behind the replaced plug. A simple enough mistake to make and a good reminder to take care when terminating around exposed electronics. If the copper had fallen on a controller the cost could have been considerable.