Insulation L/E Problems

[Pippyboy1916]

Job in a old shop, new board put in about 10 years ago, every test is fine but when we come to do the Live/Earth insulation test we get a low reading of 0.6M, now it's the same when turn off all the circuits! have dissconnected the neutral and nothing, tested from the live side of the switch to earth and THATS fine but when we try and do every circuit individually it's 0.6M (on or off) really stuck with this one!

any ideas would be great

 

[Richie Fox]

Have you disconnected each circuit cpc and phase from the DB and tested seperately?

 

[Pippyboy1916]

yes and still the same low reading

 

[andekoch]

sounds like a trapped cable in an accessory.

do each circuit separately and find the offending circuit that way then check accessories on that circuit.

 

[Pippyboy1916]

sounds like a trapped cable in an accessory.

?

done every circuit separately and the same, this is the second time this has happened too me on a job, first it was in a garage workshop, this one was in a shop!

got me fuxed

 

[zupos40]

Did you disconnect the neutrals as well, I had problems before,but not with every circuit thou, but a group of circuits and found some circuits had a neutral to CPC fault and anothers phase to neutral and by not disconnecting netral keep getting Phase to CPC faults. Fault was long screw in cable not installed correctly, circuit were functioning no breaker where tripped, found two the screws to be live.