Your thoughts.......

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Callout today - "sockets keep tripping"

TN-C-S. twin split load CU. 4 bed detached (with cellar & garage)

total no of MCB`s - 3!!!

2 of them are lighting (30mA RCD protects)

other is a 32A MCB via 30mA RCD - All sockets in house on 1 ring!!!!!!

EVERYTHING disconnected (trust me guys!)

Phase - earth reading of 70K ohms!

Eventually found an outside wall where back boxes are rusted, and copper is green :)

Take face plate off. FACE PLATE is reading 700K P-E while not attached to ANYTHING.

Could the moisture have got at the cable? N-E is good, which suggests not, but I can`t think of anything that would cause a leak of that size (it stays approx the same at 250, 500 or 1KV!)

Any input appreciated....

KME

 
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Callout today - "sockets keep tripping"TN-C-S. twin split load CU. 4 bed detached (with cellar & garage)

total no of MCB`s - 3!!!

2 of them are lighting (30mA RCD protects)

other is a 32A MCB via 30mA RCD - All sockets in house on 1 ring!!!!!!

EVERYTHING disconnected (trust me guys!)

Phase - earth reading of 70K ohms!

Eventually found an outside wall where back boxes are rusted, and copper is green :)

Take face plate off. FACE PLATE is reading 700K P-E while not attached to ANYTHING.

Could the moisture have got at the cable? N-E is good, which suggests not, but I can`t think of anything that would cause a leak of that size (it stays approx the same at 250, 500 or 1KV!)

Any input appreciated....

KME
Go back and dig up that car park and do the cable to the outside sign at the hotel!!!!!!!!!! :eek: :O:O:p:p:| :( :( :(

 
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Surely you are going to have to slog your boll**ks off opening up the circuit in to smaller sections...

the whole circuit wont be shot surely????

narrow down the dodgy bit I think....

or am I been fick cuz of Friday lubrication???

Guiness DrinkGuiness DrinkGuiness DrinkGuiness Drink

 

sparkyrj

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I have seen something similar in the past where water had got into a light switch and shorted L to E , but even when it had dried out there was still a short . I think the electricity had been tracking across the back of the switch over time, and there was a build up of carbon where it had tracked across causing a low reading to earth.

 
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