I've had some electrical problems at my house.
A few weeks ago I lost power for about 1 min (I noticed my PC and oven turned off). However, when they came back on I was aware that my lights may have stayed on. I didn't think much of it because I've had occasional power cuts and wasn't 100% sure my lights had actually stayed on (thus suggesting it may have been a momentary power cut).
A few days ago I defiantly lost power to only my downstairs sockets (which I believe is what happened last time). No breakers had tripped. I presume the RCD had tripped although the lever wasn't in the off position. After flipping some breakers and the RCD it came back on until yesterday when again I lost my downstairs sockets.
This time I unplugged everything connected to the downstairs sockets. After I flipped the breakers off, toggling the RCD (which again had stayed in the on position), flipped breakers on etc., the power came back on but would go off again with significant load (i.e., fridge or kettle).
I left it overnight and didn't touch anything. If there was some sort of earth leakage my main suspect would be the 2 gang external weatherproof socket I use for powering my mower. After unscrewing this it didn't look great inside with some corrosion, signs of water ingress (although dry now), etc. Also, the cable doesn't enter the box through a gland but just through a hole at the back. The wall sees quite a bit of weather and the way the cable has been installed it may be possible during heavy rain for some water to get into the outer sheet which is cut very close to the wall.
For what it's worth I did my best to clean the external 2 gang with contact cleaner and left it open for an hour or two before screwing the face back on.
I've got power to my sockets now but haven't put more load on the circuit that a laptop and a smart meter...yet.
Unfortunately, I couldn't see any way to isolate my external 2 gang. Although this could be a red herring I admit.
Any ideas other than spending a fortune on getting a sparky to troubleshoot? My Dad said he'd have a look but he's 82 now and I'd rather not have him burdened too much with this.
It's a period property that was rewired about 10 years ago. Doesn't look the most professional job, however.
Our Samsung fridge was causing ours to trip out a couple of years ago. It was a blocked up ice maker. Once I cleared it out it was fine.
Yeah, I really wish I could have isolated it to a faulty appliance.
Not clear from your post - did the MCB trip?
RCD will only trip on an earth fault, the MCB will trip on a short circuit.
You need to be clear as to what has tripped.
Unless it's a regular occurrence it's probably not worth investigating as if it's not happening whilst the Sparky is there, he (or she) might not find anything wrong at all.
We had a rental which had a tripping problem, Alanl (from STW, who is a Sparkie) traced it to an extension block under a fridge which was getting damp from condensation falling on it. Nothing to do with the wiring itself in the building itself.
RCD will only trip on an earth fault, the MCB will trip on a short circuit.
No MCB's tripped.
I'm assuming the RCD tripped although the lever didn't move. I dunno if it should.
I'd go the other way and suggest it's likely a sparky would be able to identify the fault if it's serious enough to trip the breaker. An RCD is more prone to nuisance/hard to trace trips.
I was thinking now that the external 2 gang should at least be made properly weathertight even if the problem doesn't immediately reoccur. I really don't like the lack of a proper gland.
External sockets normally have a place marked for a drain hole too, worth checking if it’s been drilled out.
To weatherproof the external socket a bit better.
Remove the back box and apply a good bead of silicone to the rear of it in an arc around the cable entry. Obviously a cable entry gland would be better!
As for your rcd it may be faulty. Spark out to test it properly.
I had a similar problem.
Turned out to be a faulty MCB and the RCD on one side of the unit, both just old and knackered. They wear out after a while.
We'd recently had sparks in to do the new close door buzzer and they needed to wire it into my board. After they did it my electric went off and the sparks checked the unit for me only to find just about every connection at the back to be loose, and reckoned the wiring was intermittent from that.
They were just going to leave it as the rest of the consumer unit wasnt their remit, just the wire they'd fitted themselves but I got them to do it anyway(I said was working before you started)
So could it be that and some of the wiring at the back of your unit be loosely connected, and its just one thats causing the problem.
When Some of the older style rcd’s trip the switch doesn’t drop all the way down, only to a mid position, then you have to push it down and up to reset it so you may not of noticed it had tripped.
First job, press the test button on it, see if it trips and what the switch does.
Seal round the socket leaving the bottom edge clear so if moisture does get behind it can escape.
Then with faults like this I normally suggest keeping a note of what’s running when it trips as it can be an appliance that causes it but only when it gets to a certain point, like a washing machine cycle
Yeah the test button does cause the RCD's to trip.
I've taken your advice and sealed around the top and sides of the socket box.
The fact you seem to trip circuits and they can come alive without you doing anything means somethings is wrong. It should always need mechanical intervention by you. Perhaps something is loose (rather than tripping) and the action of flicking the trips is enough to put back in position?
Presumably the external sockets are on some sort of fused spur? I would remove the fuse to isolate them while you investigate to rule out the moisture theory.
What would cause an appliance to start tripping the power? Just recently pulled out an oil rad out of storage and it's tripping the power on full whack. Ok on a lower setting. Dust? Damp?
I agree with poly ^^.
If you only have one RCD in your consumer unit and it's obvious that everything comes through it, then if that trips and circuits remain on you should be worried. If you can't isolate your outside socket from the consumer unit, you should be worried.
Some RCDs require the user to move the lever all the way to the open position before closing it again. Others get unhappy about transients and become quite trip happy, and are best reset by opening all the MCBs, closing the RCD, and then resetting the individual circuits one-by-one.
@jambourgie - is it tripping the individual circuit (like a fuse in the old days!) then it’s likely a short, either permanently there but only becoming part of the circuit when at full power or when something expands/heats up and things touch; or is it tripping an RCD (usually taking out the whole house rather than one circuit) - That would indicate that the amps going in and amps coming out (crudely described!) are not equal and so it’s finding a different route to ground. Damp could cause it. It could be something simple - but I’d probably just replace!
Update: still no good.
Lost power with a slight load on the circuit (a couple of table lamps and Xbox). toggled RCD and MCB and came back on only to go off again.
I did notice that when it went off I heard a slight 'fizz' from the consumer unit. MCB and/or RCD aren't moving, however.
Really stressed about it.
Easy option get an electrician to look at it.
it went off I heard a slight ‘fizz’ from the consumer unit.
Potentially a loose connection - but its time to get a proper sparky in think.
Sounds like loose connection if nothing is actually tripping.
Are any of the breakers getting hot?
Get someone in to have a look.
The if the circuit is only just over current it may be only after faulty item has been running for some time. Look at the case for 1<I<2. You are potentially talking minutes. If you want to be really shocked check out the curve for old fuse boards!
https://electricalapprentice.co.uk/how-do-you-select-the-right-mcb-or-rcbo/
toggled RCD and MCB and came back on only to go off again.
If you still don't know which one is tripping then stop toggling them on and off. They're opening to protect your house from burning down or potentially electrocuting you and will only operate a finite number of times.
Could be a faulty rcd.
I've also seen in the past rcd tripping when 2 different appliances where both plugged in at the same time (didn't trip when only one was plugged in).
It could have been water ingress in the socket and/or the cable itself. If it was me I'd borrow a megger (insulation resistance tester) and check the cable.
Agreed, on getting a spark out. Maybe request an EICR whilst they are there, better safe than sorry.
Have a look at any plug sockets, or extension leads. I tracked an intermittent fault to the wall socket for the fridge freezer - new socket, all fine.
What would cause an appliance to start tripping the power?
If it just trips the RCD then it could be anything, loose connection, damaged insulation, but of condensation.
I had an iron which would trip the RCD occasionally when steaming, I assume the steam was leaking internally enough to occasionally exceed the 30 ma leakage current Live to Earth. Eventually got fed up with it and stopped wearing shirts 😉
