Earth leakage circuit tripping

monkstowngirl

Hi,
We just moved into an old house which we renovated. We didn't fully re-wire but upgraded and added to system.
There is an old kitchen extension out the back where we installed a second hand Rayburn range.
Everything was going fine until the weekend and the earth leakage circuit breaker tripped. None of the individual circuits tripped on the board but when we tried to re-set the system the only fuse that wouldn't go up was the one that controls the sockets in the kitchen.
We checked the sockets for water, etc and 2 external lights also and found nothing.
The socket fuse wouldn't re-set for a few hours but then everything was ok.
Rayburn and pump seem to be working fine. This happened a few times yesterday and we thought it may have been the kettle or fridge.
The weird thing was that when we plugged in the kettle or fridge into sockets in the sitting room it tripped the earth leakage circuit.
The system was again fine after a few hours.
We thought that the problem may have been rain getting into a hole that our " great" plumber didn't fill when moving pipes. We filled the hole but still have a problem.

Anybody have any idea? At the end of my tether with this bloody house!

meercat

the problem may not be on your kitchen circuit
i would first check your immersion is switched off
then unplug everything that you dont require(wash machine,diswasher, etc)
this will help eliminate the problem
have you any external power points
unplug the rayburn pump if this re occurs and try eliminate this

monkstowngirl

Thanks for your reply Meerkat, we had electrician back to fit new rcd switch to rule that out as it was quite old. Put back on the electricity and brand new fridge is making loud shuddering noise. Unplugged it and everything else in kitchen and put on the Rayburn which tripped rcd after 1/2 hour. Left everything for 10 mins and plugged in fridge and that tripped rcd immediately. Electrician is baffled as am I. We had a look at the pump from the Rayburn and it was very hot after running for 1/2 hour.
Help!

meercat

is immersion turned off

meercat

monkstowngirl wrote: »

Left everything for 10 mins and plugged in fridge and that tripped rcd immediately!

was the pump plugged in when this happened

meercat

possible solution to help find problem
ask your electrician to install an rcbo on individual circuits if possible
this will help identify the faulty circuit
if not then leave your rayburn off for a few days and if it doesnt trip by then then its possibly a pump fault

MrThrifty

monkstowngirl wrote: »

the earth leakage circuit breaker tripped. None of the individual circuits tripped on the board but when we tried to re-set the system the only fuse that wouldn't go up was the one that controls the sockets in the kitchen.

Maybe I'm missing something here but... either a trip switch asides from the ELCB tripped or it didn't. Or did you flick down all the socket trip switches, then reset the ELCB and then flick up to pinpoint that the kitchen circuit was the issue.

I suspected the fridge immediately but it half sounds like this has been ruled out - subject to clarification.

Bruthal

They can be hard to find, these RCD tripping problems. When they are not tripping an MCB as well, its usually a neutral to earth fault, or water on a circuit somewhere, often on outside lights that were fed from socket circuits. As meercat said, often the problem in the above neutral - earth faults is not on the actual circuit that seems to cause the problem when items are plugged in.

A neutral to earth short for example, will not trip the RCD until a load is on at least one circuit, and a load on one circuit can and does trip the RCD even though the fault can be on another circuit. The load required to trip the RCD in this scenario is smaller when its plugged directly into the affected circuit, so the tripping can be very intermittent, depending on what loads are on, and what circuits compared to the problem one(s).

One way to find what circuit it may be that the problem is on is to disconnect every socket circuits live and neutral at the MCB board, identify each circuit live and neutral into circuit pairs, and meggar between the neutral and earth, and the live and earth on each circuit. This should at least eliminate circuits that have no faults on them. I would do it without plugging anything out at first, then if problem circuits are found, then plug items on that circuit out.

MrThrifty

robbie7730 wrote: »

One way to find what circuit it may be that the problem is on is to disconnect every socket circuits live and neutral at the MCB board, identify each circuit live and neutral into circuit pairs, and meggar between the neutral and earth, and the live and earth on each circuit. This should at least eliminate circuits that have no faults on them. I would do it without plugging anything out at first, then if problem circuits are found, then plug items on that circuit out.

Nice and to the point, but please OP get an electrician to do this if you're not qualified yourself...

Bruthal

MrThrifty wrote: »

Maybe I'm missing something here but... either a trip switch asides from the ELCB tripped or it didn't. Or did you flick down all the socket trip switches, then reset the ELCB and then flick up to pinpoint that the kitchen circuit was the issue.

I suspected the fridge immediately but it half sounds like this has been ruled out - subject to clarification.

Ok, to me i think the OP is possibly saying the RCD trips, and they switched off all the MCB`s, reset the RCD, then tried to reset each MCB, and one would not reset without tripping the RCD.

And as meercat has pointed out, this does not always mean the problem is actually on the circuit of which the MCB would not reset without tripping the RCD. This MCB could simply be bringing on a load big enough to trip the RCD via a neutral earth fault on a different circuit. Or it could be indeed switching on the problem circuit, which has a water problem, and/or intermittent faulty appliance or circuit fault.

meercat

cheers robbie
i was just reading back on previous thread you contributed to and you posted virtually the same reply before i got back(thats some recall you have)
maybe a sticky on how to find rcd fault

meercat

cheers robbie
i was just reading back on previous thread you contributed to and you posted virtually the same reply before i got back(thats some recall you have)
maybe a sticky on how to find rcd fault
http://www.boards.ie/vbulletin/showthread.php?t=2056037198

Bruthal

meercat wrote: »

cheers robbie
i was just reading back on previous thread you contributed to and you posted virtually the same reply before i got back(thats some recall you have)
maybe a sticky on how to find rcd fault

I dont even remember it, i thought this was the first time i thought of that:D

monkstowngirl

Wow!!! Lots of replies. Thanks a million.

Don't worry.I'm not attempting anything myself.

Well... here's an update:
Immersion is def. turned off.

The fridge is caputska. Had a service guy out and the compressor is shot to hell so getting replacement tomorrow. Could the rcd tripping have caused this damage to compressor?

Fridge and Rayburn are currently off and no tripping thus far.
I'm also getting the Rayburn specialist back out tomorrow as I want to see what he thinks about the pump as our "great" plumber put it touching a hot water pipe and it was very hot to touch last time it was on...Could this make it trip?

My head is melted and I need a fridge, cooker and heat.

Bruthal

Its not great for the fridge compressors when they are switched off while actually running, they should then be left off for 10 or 15 minutes if switched off. I had that in one of posts yesterday but pc went off, and re wrote without that part. There could of course have just been something wroing with the fridge, but they dont like power cut then supply return quickly if the compressor was running.

If you have immersion off, switch it off with the immersion switch rather than just the timer if a timer is fitted, as the immersion switch will open both L and N.

While the rayburn and fridge are off, make loads of tea:D,, the load of the electric kettle will indicate if the problem is in the sockets wiring if trips occur, or is the rayburn/pump. The pump could possibly be the problem, but the hot water pipe touching it wouldnt be expected to cause it too much bother.

paddymick

monkstowngirl wrote: »

The fridge is caputska. Had a service guy out and the compressor is shot to hell so getting replacement tomorrow. Could the rcd tripping have caused this damage to compressor?

Or maybe the fridge was the problem all along.

tunedout

if you could leave off the immersion switch permanently when you're not using it or run an extension cable (if not too messy) to another circuit that will sort it without needing to rewire etc.

monkstowngirl

Thanks Robbie. Spent the afternoon researching solid fuel stoves to keep me warm!

Immersion switched off at switch and no problems there. Made tea, ran a plug in cooker, 3 loads of washing and microwave from various sockets and no problem....
Put Rayburn on for 1/2 hr and guess what? It tripped. Think that must be the problem cos I had everything else unplugged at the time.
Ready to get a sack trolley and push it out into the front garden with a note on it saying "free" and buy myself a boiler stove which I wanted in the first place.
In the meantime, it's beans on toast for dinner cos everything else is in the bin.
Will see how I get on tomorrow.

Bruthal

The cirulating pump is worth looking at anyway, if you can run that on its own.

tunedout

robbie7730 wrote: »

The cirulating pump is worth looking at anyway, if you can run that on its own.

The circulating pump wouldn't even be directly connected to the immersion so i don't know why you would be offering up this diagnosis

meercat

tunedout wrote: »

robbie7730 wrote: »

The cirulating pump is worth looking at anyway, if you can run that on its own.

The circulating pump wouldn't even be directly connected to the immersion so i don't know why you would be offering up this diagnosis

Agree with Robbie
If you can run the pump independently it will help identify the source of the problem

Bruthal

tunedout wrote: »

The circulating pump wouldn't even be directly connected to the immersion so i don't know why you would be offering up this diagnosis

Do you have any idea how RCD`s work? If you did, the above would seem meaningless.

Post #18 indicates the immersion is isolated at the double pole switch, which is a good idea as its simple to eliminate at least the immersion unit with tripping RCD`s, but the rayburn running caused the RCD to trip, so any chance of explaining why the circulating pump needs to be directly connected to the immersion for a possible problem pump to trip the RCD?

Circuits on an RCD have a common neutral, so a neutral earth fault on one circuit can cause a load on another circuit to trip it.

tunedout

robbie7730 wrote: »

Do you have any idea how RCD`s work? If you did, the above would seem meaningless.

Post #18 indicates the immersion is isolated at the double pole switch, which is a good idea as its simple to eliminate at least the immersion unit with tripping RCD`s, but the rayburn running caused the RCD to trip, so any chance of explaining why the circulating pump needs to be directly connected to the immersion for a possible problem pump to trip the RCD?

Circuits on an RCD have a common neutral, so a neutral earth fault on one circuit can cause a load on another circuit to trip it.

if the rcd tripped it she would be able to see it directly (physically on the RCD) anyway so that rules that out. common earth is a good point alright I can see how that would trip it but to be honest i'd doubt there would even be RCD's installed in this type of house

Bruthal

tunedout wrote: »

if the rcd tripped it she would be able to see it directly (physically on the RCD) anyway so that rules that out.

What rules what out?

There does not seem to be a question as to whats tripping. Its a question of whats tripping it. Why dont you tell us, then the OP`s problem will be sorted.

common earth is a good point alright I can see how that would trip it but to be honest i'd doubt there would even be RCD's installed in this type of house

From the OP and subsequent posts, and the OP has been very clear with descriptions, id say there is an RCD in the installation myself.

They said the earth leakage circuit breaker tripped. That is an RCD. What other single breaker would trip all sockets?

Running extension leads up to the immersion wouldnt even be the solution of a diy cowboy. I think you must be having a joke or something.

You could be right though, who knows.

monkstowngirl

Hi everyone, apologies that I didn't reply. Week kind of ran away from me!
Rayburn engineer was out and had a look at it and pump. Electrician can't find fault in the circuit either. He said nothing was wrong at all. New fridge was delivered and running fine and no trips since.
it's a mystery! Only thing I can think of is external supply? We haven't gotten around to fixing the guttering and it was majorly leaking over the wet wet weekend. Where the the supply comes into the house is directly underneath the leak. Was talking to a neighbour and noticed that our external supply cable wasn't changed when the other neighbours were. Also the earth cable is a bit worse for wear. Would this by any chance effect it before I call the ESB out?

meercat

monkstowngirl wrote: »

Hi everyone, apologies that I didn't reply. Week kind of ran away from me!
Rayburn engineer was out and had a look at it and pump. Electrician can't find fault in the circuit either. He said nothing was wrong at all. New fridge was delivered and running fine and no trips since.
it's a mystery! Only thing I can think of is external supply? We haven't gotten around to fixing the guttering and it was majorly leaking over the wet wet weekend. Where the the supply comes into the house is directly underneath the leak. Was talking to a neighbour and noticed that our external supply cable wasn't changed when the other neighbours were. Also the earth cable is a bit worse for wear. Would this by any chance effect it before I call the ESB out?

an esb incoming mains should not cause your rcd to trip
the most likely cause is something internal
(maybe your old fridge hopefully)
perhaps you should get esb networks to check your supply though if you are concerned though

Bruthal

The problem with RCD trips is they can be intermittent, and if its a neutral-earth fault, it can depend on what load is on and where. As meercat says, its going to be something inside the house thats likely causing it, unless water was running into the mcb board.

As for the fridge, i think you had trips happen after the fridge was removed. Not sure what checks the rayburn engineer would do, neutral-earth faults would not stop an appliance from working. For instance, if a pump leaked a little, it could trip RCD, and if it dried then, it might not trip then, but would still work fine.

A meggar test of circuits and appliances would be a good indication of whats possibly happening.

2011

robbie7730 wrote: »

A meggar test of circuits and appliances would be a good indication of whats possibly happening.

I would agree with Robbie's post above, except I would advise caution in relation to meggaring appliances. I don't think this test would do my iMac or TV any favors :D

Also when carrying out insulation resistance tests on circuits, be careful of permanently connected electronic equipment.

The intermittent fault is always the hardest to find. In the past I found it best to install extra RCDs or RCBOs even as a temporary measure only. By a process of elimination the fault could be determined.

M cebee

meggering at 250v

between L+N (linked) and E

is how you test with appliances in situ afaik if you're troubleshoooting



but still maybe better to play safe

Bruthal

The meggar can be set to 250v or around that.

All the circuits would need to be seperated from each other, which just needs the RCD controlled neutrals disconnected from the neutral bar and the MCB`s all switched off, and meggar from each neutral to earth, and each MCB out, to earth.

No need of meggaring from L to N for an RCD tripping problem, so no impact on any devices should be seen, no matter what voltage the meggar is set to.

2011

M cebee wrote: »

meggering at 250v

between L+N (linked) and E

is how you test with appliances in situ afaik if you're troubleshoooting



but still maybe better to play safe

I can't link L+N in my iMac or TV. I could only do this with the lead in which case I would not be meggaring the appliance.

250V will be DC.
I have no idea what impact (if any) this would have on different devices and would rather not take the chance!