MCB tripping for no apparent reason

[sherlockholmes]

I think it may be electrician time to be honest, for your safety.

the RCD refused to trip even if I deliberately pushed the RCD tester

Are you saying the test button on the RCD does not work anymore?

 

[PrenticeBoyofDerry]

Like the latin by the way!

they have some lovely ladies

 

[Cigaro]

Do I set it to the right where there is the letter A with some squiggly lines beside it? If so what setting 200u, 2000u, 20m or 200m?

I'm not a sparky, but couldn't help but notice that the OP proposes to use the 'A' range on his meter - which is for measuring current, not resistance.

You must not do this - at least in the capacity in which you describe - presumably connecting the probes right across the circuit causing a dead short.

You are looking for the resistance (ohm) scale on the meter and you must turn the power off before measuring.

If you are looking for a low resistance it should be pretty close to 0 ohms.

 

[KennyB]

Sorry Sherlock, The RCD would not reset but the MCB had stopped tripping out.

The sparky was on his day off and the maintenance manager gave it to me. I will read the info you have sort carefully.

Since I disconnected the dodgy spur wire from the circuit, there has been no more tripping..... so fingers crossed!

I really appreciate your assistance and your patience!

Cheers

KennyB

 

[ban-all-sheds]

The sparky was on his day off and the maintenance manager gave it to me. I will read the info you have sort carefully.

Please do not play around with that tester - if you don't even know the difference between current, resistance and voltage you risk a large bang, damage to your installation, damage to the tester, and damage to yourself.