Pug in RDDC

[David E]

I was working for a friend yesterday on a new build. After rain the previous night the floor slab was a little like a padling pool. My mate was planing timber and you know what planer cables can get like a bit of insulation tape here and there!!!!! Anyway the cable drags through the puddle and there is a flash and a puff of smoke/steam but the RCCD didnt trip, should it have??? It was 240v planer and I suspect that it should have been 110v but am not sure of the regs on hand tool voltages.

 

[Pensdown]

I was working for a friend yesterday on a new build

If the new build is on a building site which falls under the the CDM regulations yes the power tools should be 110V. I don't know may tradesman who still use 240v tools on site but I'm sure there still are some.
THE ELECTRICITY AT WORK REGULATIONS 1989(5) Inspectors should continue to press for the use of reduced voltage lighting and power tools, eg 110v centre tapped to earth in the working environments described in para 19 of the Memorandum of Guidance leg construction work). http://www.hse.gov.uk/LAU/lacs/19-3.htm

My mate was planing timber and you know what planer cables can get like a bit of insulation tape here and there!!!!!

When was it last PAT tested?

Anyway the cable drags through the puddle and there is a flash and a puff of smoke/steam but the RCCD didnt trip

Yes the RCD should have tripped. Whats the rating, when was it last tested?

 

[SparkyMarky]

I suppose it's possible that the RCD didn't trip because it was a straight live-neutral fault with no 'leakage' to earth. Admittedly I would have thought a puddle of water on a wet building site would offer a pretty reasonable path to earth (you wouldn't catch me standing in it holding a 240V tool patched up with insulation tape at any rate!). Perhaps the water found it's way into the cable somewhere else?

If the RCD didn't trip, what cleared the fault in the end? Did an MCB on the consumer unit/distribution board trip, or did the fuse in the plug blow?

 

[securespark]

Don't go out working with your "friend" again. With a slap-dash attitude like his, who needs enemies?