Downstairs circuit tripped and now it isn't

[ouch2manyvolts]

I woke up on Sunday morning to find that the RCD had tripped that protects my:

'upstairs sockets','downstairs sockets','garage','cooker'

I reset the RCD and turned on the individual circuit breakers and all went on fine except for the 'downstairs sockets' circuit breaker which kept tripping and causing the RCD to kick in.

I physically unplugged everything from the downstairs sockets and still no joy.

I've a relative who is not an electician but is a winder so knows a bit about electrics. He got something called a 'mega' or something to check the circuit and he said there was a short between earth and neutral (I think!). We took all the sockets out and checked the wiring at the sockets but they were fine.

A couple of days later and it is now allowing me to turn the 'downstairs sockets' circuit back on without tripping it.

He say's it might either be water somewhere which has dried out or a mouse has chewed through the insulation and created a short.

Anyway, as it's now working I'm tempted to turn it back on but am a bit worried that the house might go up in flames.

Should I be worried or can I trust my circuit breakers and RCD.

It's only a 6 year old house and it's all decent kit protecting the electrics.

Looking for some advice before I potentially spend lots of cash getting this investigated.

Thanks in advance.

 

[Johnmelad502]

Ouch,

Could well be damp, (or something else) but I think you need an electrician to do the testing.

 

[bongos]

Anyway, as it's now working I'm tempted to turn it back on but am a bit worried that the house might go up in flames.

Should I be worried or can I trust my circuit breakers and RCD.

It's unlikely to go up in flames but you might just spend your life running to the RCD and switchng it back on!

Pretty decent advice already TBH. Unfortunately these sort of intermittent faults can be a nightmare to rectify.

Have you got any outside light/sockets/switches spurred from this downstairs circuit? If so, open them up and have a look. Make sure they are all completely dry and no damaged cables.

Have you put up any pictures/shelves etc where going nailing or screwing into a wall might have gone through a cable?

As your family member has already diagnosed a N/E short did he have a chance to test again now the fault seems to have disappeared?

If the problem continues then it might be worth splitting the ring up and testing it again to see exactly where the low IR is occuring. At least you can then narrow down the location of the fault to the damaged section of cable.

 

[AndyPRK]

doesn't sound like a N to E fault if turning the MCB off prevented the RCD from tripping

 

[Spark123]

Could be if the system is TN-CS, no current being drawn on the faulty circuit and no big appliances in use.
The electrician should be able to narrow it down to the cable between two sockets using the half split method, that is if it is a problem with the cabling and not something else connected in such as outside lights via FCU, boiler etc.