Intermittent Tripping

[bernardgreen]

wet between Line(live) and Neutral

will not trip an RCD.

 

[EFLImpudence]

Oh sorry, meant Line and Earth, of course. Will alter it.

 

[crystal ball]

Are there any sockets under the sink, one of my previous was caused by a leaky wast pipe and badly positioned socket

 

[MarcMCFC1986]

Are there any sockets under the sink, one of my previous was caused by a leaky wast pipe and badly positioned socket

Yes there is the washing machine ext. cable, but just checked and no leaks.

 

[MarcMCFC1986]

What you ordered there, is exactly what you already have - that switch on the left is an RCD.

RCD's are caused to trip by an imbalance of current, comparing the current passing through the live, with that through the neutral. Idea is - if they are not exactly equal, then current is leaking via some other route. The other route, could be through your body, so it trips to protect you.

What many electricians do not appreciate, is that simply turning things off (either at the socket, a switch, or at the MCB) may not prevent the RCD from tripping, if the leakage is neutral to earth leakage. Such faults, especially if intermittent can be very difficult to find. Begin by unplugging anything which can be unplugged, then see if it still trips. If there is no trip of the RCD, then you can gradually add things back in.

If still trips with everything unplugged, then you need some expert help from someone who knows what they are doing, with an insulation tester. That person is obviously not the first 'electrician' you discussed it with. Common causes are oven elements failing, immersion heater elements failing and water which has got into an outdoor light.

Thank you for your message. The idea of ordering that was to plug in one appliance at a time into it in the hope that it would be the adapter that trips off and not the whole circuit - and eventually know specifically which appliance is faulty.

Sounds like it wasn't a good idea though. It's just been delivered so I'll send it back tomorrow.

 

[Harry Bloomfield]

Thank you for your message. The idea of ordering that was to plug in one appliance at a time into it in the hope that it would be the adapter that trips off and not the whole circuit - and eventually know specifically which appliance is faulty.

Sounds like it wasn't a good idea though. It's just been delivered so I'll send it back tomorrow.

When have two RCD's in series and of the same trip rating, either one or both can trip.

 

[JohnW2]

When have two RCD's in series and of the same trip rating, either one or both can trip.

Indeed. In fact, even if they have different trip ratings, there's no guarantee that the lower rated one will trip first and/or be the only one to trip.

Kind Regards, John

 

[EFLImpudence]

Edited when noticed it was an active RCD.

 

[MarcMCFC1986]

Hopefully Final Update: The electric stayed on overnight last night. Just before going to bed I tried to plug the Dyson Hoover back into the plug socket that is next to the back door (where I suspected the water was coming in) and that socket is now completely dead. The rest of the house, including the kitchen, is still on and working fine - so it must have been water finding it's way through a crack in the wall to that socket and tripping the circuit. Trying not to count my chickens just yet as it did take a few days for it to trip off last time - but I'm fairly confident that the blocked drain/water cascading down the wall was the issue.

Thanks everybody for your help/advice - I've genuinely learnt a lot!

 

[winston1]

Just before going to bed I tried to plug the Dyson Hoover back into the plug

Thanks everybody for your help/advice - I've genuinely learnt a lot!

Is it a Dyson or a Hoover? It can't be both as they are different manufacturers.

I should wait a bit longer before deciding you have cracked it. No insulation tests have been done after all.

 

[MarcMCFC1986]

Is it a Dyson or a Hoover? It can't be both as they are different manufacturers.

It's a Dyson Vacuum. I just grew up with the word 'Hoover' being used to describe the thing you push around to pick up debris off the floor, regardless of manufacturer.

See - I'm always learning!

 

[Harry Bloomfield]

You (or someone) need to work out why that socket no longer works. It seems a bit of a stretch to me, for it to simply become dead and cure your tripping RCD issue.

How do you know it is dead? It could just be the socket has failed and the cable supplying the socket remain live.

Maybe the supply has failed at where ever it is fed from? If it is a socket added later than the main installation was fitted, it will probably be a spur (single cable in the back), rather than on the ring (two cables in the back). If its a spur, trace its supply cable to find where it has been spurred off the ring and if you are confident it is the cause of your RCD trip, disconnect it from the rest of the ring.

 

[MarcMCFC1986]

You (or someone) need to work out why that socket no longer works. It seems a bit of a stretch to me, for it to simply become dead and cure your tripping RCD issue.

I was assuming it was dead because water was getting onto it.

 

[crystal ball]

I would check it out as a matter of urgency, with all power off

 

[JohnW2]

I was assuming it was dead because water was getting onto it.

Other then when the water results in an RCD tripping, there is no reason why the presence of water should make a socket 'dead'. As has been said, this matter really should be investigated as a matter of some urgency.

Kind Regards, John