Garage RCD keeps tripping

iamchris · 18 May 2020

Hi all, many months ago I had a hole in my garage roof that let in a lot of rain water, now fixed and dried out a long time ago.

I'm not certain if related but ever since around that time the garage RCD circuit has been tripping. There is only one plug socket in there and it still happens when everything is unplugged. When I flip it back on it generally stays on all day but then trips again during the night.

I'll be getting an electrician to take a look after lockdown but anyone any ideas? If it helps the consumer unit is in the kitchen. There's then an armoured cable buried in the back garden which feeds one double socket in the garage.

Many thanks

terryplumb · 18 May 2020

Is it an RCD ,or an MCB that trips ?
And is it part of the consumer unit in kitchen ,or located in the garage ?

crystal ball · 18 May 2020

Have you looked inside the socket?

iamchris · 19 May 2020

Hi sorry I'm not sure of exact terminology so here is a picture. The one in the middle labelled garage is what trips, this is located in the kitchen. There is nothing else in the garage other than a plug socket. I have looked inside the socket which seemed fine but replaced the face plate anyway.

ericmark · 19 May 2020

It seems likely there is a junction box where the cable changes from twin and earth to SWA I would hunt for that box, the device you have is called a RCBO and it both tests for over load and earth leakage but unlikely it is over load. It would seem since over night I will guess there is some joint with a hole in the bottom so as it cools is sucks in water, and when it heats up again it blows it out, it has likely causes a carbon track so slightest amount of water will allow enough current to flow to earth to trip it, it needs a 500 volt tester to be sure one has found the fault, but with power off cleaning inside any enclosure with wet wipes may remove the carbon track. It could be inside the socket, I would change socket if you can, I found one in my flat under house which had been damaged with water, but on outside only sign was a little discolouring. Worth a go changing it.

iamchris · 19 May 2020

Thank you for the info there! I will take a closer look over the weekend. Most likely I'll need to get an an electrician in but it gives me some idea.

Thanks

ericmark · 19 May 2020

Every time I hear the TV advert for low carbon electric I wonder how it is made, as as far as I am aware any electric arc is likely to form a carbon track and it is all to do with the material the insulator is made from rather then the electric used, never quite understood where the carbon comes from, the first I remember was as an auto electrician and it would be attracted by crack in the distributor cap and only way to keep it running was to drill a hole through the carbon track.

So it is likely you do have a carbon track some where, and if you can't see it, then change the socket, as most likely it is inside the socket.

AndyPRK · 19 May 2020

An RCBO I note

terryplumb · 19 May 2020

Don't you have any lights in the garage ??

iamchris · 19 May 2020

terryplumb said:
Don't you have any lights in the garage ??

There is one but it just plugs into the socket. It's unplugged most of the time and trips when not plugged in.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Garage RCD keeps tripping

Similar threads