Earth Leakage trip switch

[pdallimore]

I've got a problem with an earth leakage switch. Our house had a granny flat built on about 19 years ago, the power supply is from our house, but it has it's own meter, fuse box and earth leakage switch. Every so often this switch will sound as though it is shorting (a gentle crackling) then it will trip.

after about 5 minutes it can be reset and will work OK for a few days/weeks, depending on what mood it is in. Could it be a faulty trip switch?

 

[breezer]

it could be but unlikeley, best get an electrician in to test the installation

 

[spark]

I have come across it before and it was a faulty RCD; you may find eventually it just won't reset. If the installation has not undergone a periodic test and inspection, then get it done. It should cost no more than £100 if it's only a 'granny annexe'. The RCD I had a problem with was some years old and when tested with my RCD tester it did not trip on any trip current, right up to the 5x trip current (150mA). It too had an arcing problem and would not reset after a short while. It will give you more of an idea if you can find a BS number on it. If there's no BS number or earth leakage trip current (it should say 30mA) then it's likely to be well in excess of 20 years old and could well be the RCD.