About a month ago i ran a spur to feed a socket in my garage,after
connecting and checking i switched on mains supply.The mcb that supplies the
ring the i was using sparked and tripped out,after checking all connections
that i had made i tried again.This time everthing seemed ok with no trip.The
trouble i am having now is that the same mcb trips out about once a week for
no reason.This has happened twice in the middle of the night with no
switches used.An earlier request for help for a similar problem suggested a
fridge/freezer coming on to be the cause,the mcb i am having trouble with is
not on the same circuit as any of the kitchen appliances so this could not
be the cause. I will be gratefull for any theories about my problem
..Thanks for any replies KEITH

Swap it with another same value MCB on the board and see if the problem moves
or not - that will say whether the problem is in the MCB or on the circuit it
is supplying

Nick

"keith" wrote in message
...
About a month ago i ran a spur to feed a socket in my garage,after
connecting and checking i switched on mains supply.The mcb that supplies the
ring the i was using sparked and tripped out,after checking all connections
that i had made i tried again.This time everthing seemed ok with no trip.The
trouble i am having now is that the same mcb trips out about once a week for
no reason.This has happened twice in the middle of the night with no
switches used.An earlier request for help for a similar problem suggested a
fridge/freezer coming on to be the cause,the mcb i am having trouble with is
not on the same circuit as any of the kitchen appliances so this could not
be the cause. I will be gratefull for any theories about my problem
.Thanks for any replies KEITH

About a month ago i ran a spur to feed a socket in my garage,after
connecting and checking i switched on mains supply.

Did checking include measuring the continuity (with a specialised tester
that provides 200mA of current), insulation resistance (with a specialised
tester that provides 500V DC) and earth loop impedence (with a specialised
tester that pulls 20A down the line)?

If not, obtain said testers (or an electrician) and see what the results
are.

Christian.