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Fuse box tripping out

The main trip switch keeps tripping out for no apparent reason?! Nothing is being switched on at the time when it trips out. I have tried working out what the cause is by switching all the individual circuit switches off and then putting them back on one by one but have been unable to identify the cause as it doesn’t cause a trip. It normally trips in the morning but has done it at other times throughout the day. Sometimes it trips everyday and sometimes it can go a week or so without tripping. This has been going on for months now.

5 Answers from MyBuilder Electricians

Best Answer

Sounds like your 'Main Switch' is an RCD. There are three reason an RCD will trip:
A) there is a fault with the fixed wiring
B) there is a fault with equipment connected
C) there is a fault with the RCD

C is very rare and unlikely to be the cause but always worth checking that is operating correctly.
B is the most likely cause - the usual suspects are appliances with heating elements.
A is less likely but can happen if there is damage to the fixed wiring or water ingress. Usual suspects are outside lights and junction boxes. Rodents can also cause significant damage to cable.

The solution is to engage the services of a good electrician with the right test gear to diagnose and solve your problem.

Hope this helps a bit.


Answered 23rd Feb 2019

You need an electrician to test the rcd for functionality, and carry out some insulation tests to identify where the fault lies. Won’t take a decent sparks long to identify.


Answered 23rd Feb 2019

Unlikely to be RCD at fault. An electrician, armed with a multi function tester, bit of common sense and the fault can be rectified.


Answered 24th Feb 2019

It is very unlikely to be a faulty RCD unit,
There is more likely to be a fault on the fixed wiring
Or an appliance that is plugged in often fridges,washers in my experiance.
An insulation resistance test on each circuit, carried out with a multi-function tester should definately narrow it down and find the problem,i hop this helps,kind regards


Answered 26th Feb 2019

Refrigeration appliances can also cause this when the compressor kicks in

You need the electrical wiring and the appliances checking with an insulation meter, colloquially known as a megger. This will identify any low insulation readings on any of the appliances, circuits.


Answered 28th Feb 2019

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