ever seen a blown cut-out fuse?

I got called out by a plumber who thought he had blown the  main fuse. I was able to confirm he had.


He was fitting a aluminium shower screen when part of the frame went behind an extractor fan and went bang.


I found he had drilled one of the frame screws through a concealed cable running diagonally across the wall he had tilled which made the frame live when he started fitting it, when he pushed it behind the extractor it contacted the earthed metal frame. The old 32A Wylex MCB did not trip but the main fuse did.


What was more worrying is what would have happened if he had not pushed the frame behind the extractor.


Later when fitting a new RCD protected CU the overhead supply pulled a massive lump of masonry off the chimney when a tree branch fell on the OH line a few poles away.

I got called out by a plumber who thought he had blown the  main fuse. I was able to confirm he had.


He was fitting a aluminium shower screen when part of the frame went behind an extractor fan and went bang.


I found he had drilled one of the frame screws through a concealed cable running diagonally across the wall he had tilled which made the frame live when he started fitting it, when he pushed it behind the extractor it contacted the earthed metal frame. The old 32A Wylex MCB did not trip but the main fuse did.


What was more worrying is what would have happened if he had not pushed the frame behind the extractor.


Later when fitting a new RCD protected CU the overhead supply pulled a massive lump of masonry off the chimney when a tree branch fell on the OH line a few poles away.