No earth or neutral

[philipbg]

Went to customers house yesterday (TT System) with a reported loss of power to the outbuilding.
Checked the main consumer unit & the mcb was off, so flicked it back on, plugged in the megger & it showed 230v. But when I tried the lights or plugged in the Strimmer nothing happened, when tested I had 230v between live - neutral, live - earth at the outbuilding consumer unit.
So I thought I would checked the main board only to discover the neutral & earth were disconnected, reconnected the cables & success.
What I don't understand is that the customer said the power was fine up to a few months ago & then nothing, he didn't do anything & no one else has been playing, so first of all why was it working without a neutral & earth connected & then why did It suddenly stop working.

 

[ImpededLoop]

Probably a neutral - cpc fault on the cable causing an upfront RCD to operate. Someone has disconnected it to remove the fault.

The outbuilding probably worked with the neutral and cpc disconnected due to the neutral current being diverted through extraneous metal parts in the outhouse.

Was there an RCD and did you test it?

Suspect the customer forgot to mention that it had been disconnected by a previous electrician.....

 

[philipbg]

Probably a neutral - cpc fault on the cable causing an upfront RCD to operate. Someone has disconnected it to remove the fault.

The outbuilding probably worked with the neutral and cpc disconnected due to the neutral current being diverted through extraneous metal parts in the outhouse.

Was there an RCD and did you test it?

Suspect the customer forgot to mention that it had been disconnected by a previous electrician.....

RCD was working fine & there was no earth neutral fault when i tested the cable.

 

[davesparks]

You say the earth and neutral were disconnected and the customer says it was working and nobody has done anything to it.

Both cannot be true.

Someone has disconnected them.

My first guess would be that the customer knows they were disconnected, probably by an electrician after finding a fault and they probably disconnected the live too.
The customer has reconnected the live thinking that's all they need to do and realised it doesn't work, so they call a different electrician and play dumb.

 

[DPG]

You say the earth and neutral were disconnected and the customer says it was working and nobody has done anything to it.

Both cannot be true.

Someone has disconnected them.

My first guess would be that the customer knows they were disconnected, probably by an electrician after finding a fault and they probably disconnected the live too.
The customer has reconnected the live thinking that's all they need to do and realised it doesn't work, so they call a different electrician and play dumb.

I think Dave has nailed it.

 

[philipbg]

You say the earth and neutral were disconnected and the customer says it was working and nobody has done anything to it.

Both cannot be true.

Someone has disconnected them.

My first guess would be that the customer knows they were disconnected, probably by an electrician after finding a fault and they probably disconnected the live too.
The customer has reconnected the live thinking that's all they need to do and realised it doesn't work, so they call a different electrician and play dumb.

I did have my doubts, but the poor sod struggled to walk, so it wasn't him & the CU had a nice layer of dust on it.

 

[ImpededLoop]

RCD was working fine & there was no earth neutral fault when i tested the cable.

So you were getting 230V to neutral and cpc when they were disconnected, yet there's no fault?

 

[telectrix]

I did have my doubts, but the poor sod struggled to walk, so it wasn't him & the CU had a nice layer of dust on it.

well there's your answer. dirty dust with metallic filings in it, providing a path for the electrons. but did the meter register this?
think this situation is a case of customer telling porkies.

 

[philipbg]

So you were getting 230V to neutral and cpc when they were disconnected, yet there's no fault?

I know, strange!

 

[davesparks]

I did have my doubts, but the poor sod struggled to walk, so it wasn't him & the CU had a nice layer of dust on it.

Someone must have disconnected them, and if it hasn't been opened in a long time it must have been disconnected a long time ago.

 

[Zerax]

I did have my doubts, but the poor sod struggled to walk, so it wasn't him & the CU had a nice layer of dust on it.

That old trick wouldn't have fooled Lieutenant Columdo...

 

[captaincaveman]

This sounds fairly familiar to a job I did a while ago in an office toilet where the metal ceiling frame was sparking when the lights were on. I eventually discovered the cpc to the lights was broken above the ceiling before the toilet lights... Then the switch wire was pierced at the light switch by the screw... And to finish off the neutral for the lights was disconnected at the ccu (presumably to stop the mcb tripping due to the ir fault?).
The result being the lights had been operating for god knows how long by way of using the building structure as the neutral...

 

[Kidsolo]

Maybe a previous electrician disconnected due to non payment of invoice