Mains trips

[James76]

For some time we have had a problem with our mains tripping for no apparent reason. The circuit board does not trip any individual fuse just the complete mains. It can happen as recently as 3 times in as many days or nothing for a month.
Any ideas please?

 

[Steve]

An earth fault.

PS If you're in the USA why are you posting in "Electrics UK"?

 

[James76]

Not in USA that was a mistake that has now been corrected!
If it is the earth what is the best way to fix it?
Many thanks

 

[ban-all-sheds]

You need to find what's causing it first, and that can be a right PITA.

After a trip does it all go back on without any problems?

Start making careful notes of exactly what is on when it trips, or had been on recently before, and where people are in the house.

And what the weather is like, or had been recently before.

Start unplugging items or turning off circuits to see if it stops, although with it so erratic and possibly weeks apart that probably won't do much good.

Has it always done this to you, or was it fine for years? Think back to any work that was done not long before it first happened, or any new appliances installed?

Do you have a split-load CU, or is everything on a single RCD incomer? Any spare ways in it?

 

[Steve]

Trial and error! One of your appliances or fixed accessories is leaking current to earth intermittently.

Favouries for earth leaks:

boiler
washing machine
kettle
immersion heater
any "wet" appliance - uses both water and electric
wires under ground floor boards submerged
pond pumps
outdoor electrics
dodgy wiring
faulty RCD (the switch that trips)


Its worth mentioning, the switch that is plunging you into darkness is PROBABLY an RCD, and only trips when you have a small (or large) earth leak, it is VERY sensitive, and it is not advised to have them protecting the whole house, for the very reason you are experiencing. It may be worth asking a recommended electrician to look at it and see if he can upgrade your existing board, or replace it with something more suitable.

 

[Steve]

damn it ban all sheds! That was inevitable, think we been following each other

 

[James76]

Thanks for all info.
It has been going on for some time we went away at Xmas expecting it to trip but surprise nothing until we got back. When we were away we left nothing on standby so maybe it is something to do with that. We had thought of getting the circuit board changed.
The weather does not seem to have any effect on why it trips.

 

[sm1thson]

mice are a distinct possibility (they will pass under the floor of your house more than you think no matter how clean you are).

 

[JohnD]

this is what we call "RCD Nuisance Tripping"

Most often caused by "watery" appliances such as kettles, washing machines, electric showers, immersion heaters, boilers and CH pumps, outdoor electric points or lighting exposed to rain; appliances with heating elements such as ovens; or rodent damage to underfloor cables.

Start by UNPLUGGING all appliances; see if the tripping stops. If so plug in half of them and see if it starts. If not, unplug the first half of your appliances and plug in the other half. This will enable you to identify faulty appliances.

It is a common problem
see
http://search.diynot.com/forum_sear...it=drop&since=any&author=&search=Search+Forum

If the whole house is losing power on all circuits this indicates poor design.

please post a photo of your consumer unit, meter, company fuse, incoming main and the various cables around them (especially any green and yellow ones)

do you live in the country with an overhead supply line?

edit: far too slow[/i]

 

[ban-all-sheds]

damn it ban all sheds! That was inevitable, think we been following each other

I wondered who was taking my temperature....

 

[ban-all-sheds]

It can also be caused by a leak of the watery kind getting into a socket - someone recently posted here and that turned out to be his problem. It was a small leak down the back of the bath from a shower, but it took a while to trip, as there was the delay while it trickled through the floor. IIRC with short showers, or warm weather he got no trips.

Good luck!

 

[TicklyT]

Fridges can be among the usual suspects of 'watery appliances'

Frost free fridges run a defrost cycle, and melt water is often fed into a tray on top of the motor to be evaporated off by the normal working cycle.

Occasionally the tray overflows, and the motor is underneath it.....

 

[Click-Sure]

Neutral Earth faults in extension leads and 4-way-splitters was a bit of a favourite for me last year.

On the first one I spent nearly a hour with the Megger trying to find it (well hidden)