RCBO tripping out

[Davethesparks]

Had a call from a client
RCBO feeding socket outlets would not stay made live
Even with no appliances plugged in.
Arrived and tested the circuit to find a phase/cpc short
Broke the circuit down to find that both legs of the ring from the board
Showed the fault
Disconnected the RCBO tested the legs of the ring to find the fault cleared
Turns out the fault was in the RCBO it self
Never come across this before has anyone else ?
Dave

 

[aaron1984]

Hi,

This has happen to a mate of mine with a RCD when we were doing our fault finding in the pre-exam training at our college and the teacher said to us that it's a nightmare when this happen as all the electricians don't expect such fault

 

[Davethesparks]

First time in all my 35 years i have come across this

 

[aaron1984]

lol imagine how we felt being students.

by the way are you looking for any electricians mate/improver as i have just passed my 17th edition and Part P but am really struggling to find someone to do my NVQ Level 3 with.
I'm really not concerned about wages

thanks

 

[Davethesparks]

Not at the moment fully staffed for now

 

[aaron1984]

Ok mate,

thanks anyway

 

[Sintra]

Had a call from a client
RCBO feeding socket outlets would not stay made live
Even with no appliances plugged in.
Arrived and tested the circuit to find a phase/cpc short
Broke the circuit down to find that both legs of the ring from the board
Showed the fault
Disconnected the RCBO tested the legs of the ring to find the fault cleared
Turns out the fault was in the RCBO it self
Never come across this before has anyone else ?
Dave

Had the same problem once a few months back. Call out to sockets not working in a bar.
RCBO was tripped and would not reset so split ring, done all usual tests could not find a problem.
Eventually disconnected all cables at dist board and tried to energise RCBO and you guessed it would not energise.

Was the RCBO in question an MCG brand?

 

[Davethesparks]

Yes it was funny that might be a build defect ?

 

[Sintra]

Had a few problems with that particular brand.

 

[billy110]

I have had this quite a few times with both rcd's and rcbo's, mainly defective wylex units. I have fitted 3 rcbo's which were defective straight from the wholesaler! On 2 the test button wouldn't operate and the third went poof and deployed smoke when energized! I think they must have been knocked together in China!

 

[super_stuey]

Just a thought on this subject, our college is now teaching us to IR test from the bottom of the RCD through the relevant circuits due to the possibility of damaging the RCD with 500v.

Not that I really agree but they mite have a point you never know. Bit annoying doin it twice tho