RCD tripping at night in windy weather

mossym

the RCD in my house keeps tripping over night when we have heavy rain or wind outside, so has happened a few times last couple of weeks. never happens if it isn't raining or windy. any ideas what may be causing it?

10-10-20

Have a look at this: http://boards.ie/vbulletin/showthread.php?t=2055274085

mossym

cheers, no cables going outside that i know of though, will check the outside lights for water, but even wind with no water seems to trip it.

is it possible for the rcd to trip if the mains coming to the house is erratic?there have been problems in the neighbourhood with power going before

10-10-20

Only if you have a high load on the mains and the startup currents exceed the rating of the MCB. If it's one specific MCB then it's unlikely.
You should also check for damp patches in ceilings and under carpets too.

sparkfireman

it has nothing to do with the mains... the esb side is fine.... its to do with ur stuff... something like sockets or a shower or something... hmmm... meditate on this i will....

Are u sure theres nothing outside? And it only happens in the rain!??? Its seems like if its damp getting into a neutral - earth somewhere.... its not a live - neutral or a neutral - earth problem.... cos that would bang... The next time it happens u need to shut down mcb's to the right of the RCD to try and localise the fault to a particular circuit...

Love fault finding i do!

ATB

JOE

Dotsie~tmp

First, have you ever been able to get to the board while the fault was still present? If you can, shut off all the MCBs that are on the RCD (they should be all or mostly 20 Amp rated). Then the RCD should set. Now one by one push up ("close") the MCBs. The one that trips the RCD as u set it is the faulty circuit.

Note: This is not guaranteed to find the fault.
-First the fault must be still present (intermittent RCD faults are bastards to find).
-There always the possibility of a faulty RCD (unlikely i find).
-Earth/Neutral faults can make it seem the faults are on multiple circuits.

mossym

update, happened again the other night but time in the evenign while we were watching tv, no wind, no rain, and no other breakers tripped. went straight to fuse board and reset rcd and it was fine. means fault was only momentarily. no showers, washing machine or anything was on, in fact, the only thngs that were on are never on when this usually happens during the night.

Dotsie~tmp

Things don't have to be switched on to be faulty, just plugged in (see earth/neutral fault). For a few days, before you go to bed unplug everything, and i mean everything (a huge pain i know) and see if she trips. If the RCD goes while your there ask anyone did they just turn on or plug anything in or run any water. Also do you have a time clock that runs some form of water heater or immersion at night? Run those elements a bit, both bath and sink to see if they are healthy.

If a week or two of this give you no joy you may need to contact an electrician to meter the installation to see what they might find. Because its intermittent and it may be caused by an appliance they may find nothing and still must be paid however.

sparkfireman

Dotsie~tmp wrote: »

First, have you ever been able to get to the board while the fault was still present? If you can, shut off all the MCBs that are on the RCD (they should be all or mostly 20 Amp rated). Then the RCD should set. Now one by one push up ("close") the MCBs. The one that trips the RCD as u set it is the faulty circuit.

Note: This is not guaranteed to find the fault.
-First the fault must be still present (intermittent RCD faults are bastards to find).
-There always the possibility of a faulty RCD (unlikely i find).
-Earth/Neutral faults can make it seem the faults are on multiple circuits.

lol like i said!

Antenna

a long shot but could current be leaking from a VCR, TV (or anything connected) to the TV aerial cable, and on to an outside TV aerial - which would pass more current to earth when damp

Stugots

My parents had a similar problem a while back. Two separate electricians came and investigated without any result. Finally a leak in the immersion showed that the immersion element was faulty and that was the culprit. Might be worth having a look around the immersion to see if there is any dampness.

Bruthal

Dampness can cause trips between live earth on an rcd contrary to earlier ideas sayin that would bang, it may not bang as water can sizzle away and trip an RCD without any bang.

Usually this would be on circuits going outside. If an individual socket was added or replaced inside and nuetral and earths are swapped -ie earths into neutral and neutrals into earth terminal then it will trip RCD if something is plugged into just that socket. Also a neutral earth short in the house would case an RCD trip but only when something somewhere is plugged into a socket on that circuit. Immersions can get moisture in them sometimes. Does immersion have timer and possibly thats tripping it when timer brings it on.

Were any outside lights added to outside house as they can sometimes be fed from socket circuit and water in it could trip.

I replaced a fuseboard in a house a few years back and the RCD was tripping on new MCB board. Even with Main switch off it tripped, so even with power off into house it tripped. That was a bit of a brain teaser to find and sort

joebre

Had problem when RCD tripped and would not reset. Turned off all the MCB's and put them back in one at a time. Located fault in utility as RCD would trip immediately this MCB was reset. Checked appliances there, one at a time and found faulty washing machine. Left plugged out until it was repaired.

Now have similiar problem but intermittent. RCD trips but goes back when reset. Once or twice, it would not reset and traced MCB to some kitchen appliances. Cannot find fault with these appliances. It often happens when we are out of the house, as the appliances are not being used. I also have some outside lights, on an extension lead. It is covered bit liable to dampness !
Wondering what can be done, in terms of testing, or it it a case of plugging things out over a period of a couple of weeks to track the problem ?

Joe

Bruthal

Sometimes intermittent rcd tripping like than can be dampness, often with outside lights if they are wired from socket circuits, I often do connect them to a socket myself via a fused spur and out to the light

did you notice it getting any worse after rain, are the outside lights a permanent setup but supplied by extension lead and just plugged in? Are extension plugs out on the end of this lead?

joebre

Outside lights are 2 LV transformers, plugged into an extension lead. I am waiting to drill wall for waterproof socket. RCD could trip several times a day and then not trip for a week. Not noticed link to rain/dampness but it would be easy to plug out lights for a few weeks to check !

Joe

Bruthal

yes id say thats probably the problem, plug them out and see,
Are they garden lights,

joebre

Yes, they are.
Led's in deck and around garden.
Usually switch off at night but will plug them out now.

Joe

Bruthal

If you are switching them off at the socket usually thats good enough, usually dampness not enough across neutral and earth to trip RCD, usually need neutral and earth touching for it to happen, especially if not much other stuff on in the house, but its not beyond posibility, other stuff being used in other sockets can increase the chance of neutral earth problem tripping the RCD, maybe you find they dont trip once the socket switch is off

plug the lights out for a week and see what happens anyway

You`d be better off wiring them out more permanently if the lights are permanent, from a socket into a switched spur then out to a weather proof method of connecting into the transformers for the lights.

anyway hope that sorts it by plugging them out

joebre

Outside lights plugged out since last Tuesday. Been very damp/wet. Not tripped since. Will give it another couple of days to be sure.

Will upodate later in week.

Joe

joebre

It was too good to be true !

As posted above, the outside lights were plugged out for the last 8 nights.

No problem at all.

Left house for an hour today and when I came back, the RCD had tripped. No one in house at the time.

Only devices on were laptop, fridge/freezer, separate fridge and a coffee machine. The coffee machine stays on for an hour after making a cup. I had a cup before I went. I suspected it before as I had trouble a couple of times trying to reset the MCB that controlled the coffee machine

I will have to go back to the trial and error again or is there any test that I can have done?


Joe