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Rcd tripping when appliance is switched on.

I have a spur circuit off the distribution board. When I plug in and switch on an appliance, it trips the RCD. It's done it with a drill and with a vacuum cleaner, both of which cause no problem on the ring main.
I've re-wired the spur (it's only about 2m from the board), and it's still the same.
I've replaced the MCB on the circuit with a bigger one, and it's the same.
Any ideas?

2 Answers from MyBuilder Electricians

So you changed the mcb for a bigger one, even though it’s the RCD that is tripping? You are putting yourself in danger by doing this as the mcb trips on overload and the RCD trips on an earth leakage fault between live and neutral. By upping the rating on the mcb the cable could overheat and possibly burn your house down. I would strongly recommend you get an electrician in with test equipment to check all this out. It’s highly unlikely to be a faulty RCD or mcb. As it’s a diy job I think you may have something wrong, all circuits are dead tested BEFORE energising when a professional does it.


Answered 15th Sep 2018

It could be earth leakage

If the hole house is on one RCD the earth leakage could be on a different circuit but when your putting your appliances on it could be just enough to push the RCD to trip.

Best way to solve this issue is to get a registered electrician to put an earth clamp meter on and find out if this is the issue then if so to narrow it down and find the culprit.


Answered 16th Sep 2018

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