Earth goes bang!

[Khan]

Hi all. Just went to a property where the water and taps were given a shock to the house occupiers. The boiler was cross bonded and had a bonding conductor run to the MET. But however surprisingly the property did not have the main earth. So I had connected a 16mm earth to the ccu and when I was connecting it to the met, it went bang when the 16mm came in contact with the met and let off a little spark. What could this be? The electric was on while I done it, the occupier a has relatives over so could not turn it off.

 

[Plonker 3]

IMaybe not given the OP’s response so far.

Maybe he went to was the pots after his tea!!!!

 

[nickblake]

I really can’t believe I’ve read this!

Marvo, regardless of the forums wish not to upset members, this guy is a liability!

I wouldn’t give a ---- if the Queen was guest of honour, disconnect until the fault is found.
I take it this fault is resent or have they had a pair of marigolds handing at the side of each tap since moving in.

On a practical note. Sounds like a N→E internal fault in conjunction with a high resistance supply neutral. I take it there’s a functional RCD? Maybe not given the OP’s response so far.

exactly my thoughts right down
to the queen

 

[GLENNSPARK]

Maybe he went to was the pots after his tea!!!!

well...lets hope he wasn`t representing any potential...

certainly wasn`t with a brain dead post like #1

 

[sparkyphil1]

There's a possibility of a supply fault but it's a long shot compared to the problems being on the consumer side. As stated sort out the main earth fault(s) and test the incoming supply first followed by bonding where necessary followed by testing the circuits etc. There's a good chance there's going to be more than one fault so be methodical and don't skip anything.

The installation is very unsafe at the moment so it needs immediately isolating to prevent someone getting injured. If you're even a little unsure of the testing procedure please get assistance from someone with more experience.

"So say all of us!" Lol there wasn't upstairs a room you couldnt get into? And motorbike outside and a BBC crew hiding in the cupboard?

 

[Silly Sausage]

exactly my thoughts right down
to the queen

If they were Royalty, I'd have left it be and said 'Carry on as you were my Worships.'

 

[ChrisElectrical88]

I came across the same thing at one of my friends dads house, it had been like it for years he had just got used to getting a nice belt everytime he used the kitchen sink (112v if i remember correctly)! I started by isolating, testing Ze to confirm a earth was present at the property, r2 tests to bother bonding points, then IR tests to each circuit, turned out he had a N-E short, RCD faulty, traced it to an earth been used as a N at a double pole switch. I still don't fully understand how i corrected the fault as i was only a young nipper at the time and cant think back properly on what i did, however when i was finished i did a full set of tests to all circuits which were fine and the sink was no longer giving away free shocks!