MCB in on position, but still have broken circuit

[thinkwallet]

Hi,

Sometimes my 6amp MCB trips when a bulb blows, however, this time my son switched on a light upstairs and a bulb blew, but the MCB did not trip but the circuit is broken.

Is the MCB itself blown? Can it fail and stay in the on position?

I have a spare to replace it, but don't wish to proceed unless I know that the most likely explanation is that the MCB is faulty.

 

[securespark]

Have you got a voltage on the circuit?

 

[RF Lighting]

Depends on the make.


Try turning the MCB off and then back on again.


Do you have a multimeter which you could test the existing MCB with?

 

[thinkwallet]

Got a bloke in, he fixed it.
I was right tho' it was a faulty MCB.
For God sake don't stop replying to these questions!