mineral insulated cable repair

[roland1976]

hi there i was looking for some advice please. i have micc installed in a sandstone turret it get damp occasionally when not vented window open etc. recently the light circuit has tripped the lights still work and after aprrox ten mins it trips again. suspected damp in the mineral.
can you chase out the moisture ?
could i use ipv rated light switches in the future to prevent any moisture getting in?
or is if its done correctly should you get any moisture in the cable ?
any help and advice would be deeply appreciated as i m finding it hard to find anyone to sort it for me
many thanks rol

 

[gnselectricals]

If it is mineral insulated with the correct pots and glands then it should be bomb proof, unless there's cable damage allowing water ingress. Is it surface mounted? Would recommend a sparky to test and visually inspect where possible

 

[davesparks]

Firstly it needs testing to establish exactly what the fault is.
Then if it is in the MI itself then yes the moisture can be driven out by opening up one end and warming the cable up to drive it out. It'll then need reterminating correctly.
Unless the cable sheath has been damaged then the only way damp can get in is through a failed termination.

 

[shanky887614]

it is probably more likely in the switch, if micc is made off properly then you wont get moisture inside it (unless the copper has been damaged)

 

[telectrix]

inclined to agree with shanks. @OP, does it trip with the lights switched off? if not, it's unkiley to be the micc.

 

[Pete999]

Try and remove the MICC from the switch enclosure, and gently heat the sheath from about 12 inches from the gland, if damp has got in to the cable you should see an increase in the IR as you heat it.

 

[roland1976]

thanks for the advice guys . yes it is wall mounted and it tripps when the lights are off . i had a sparky come round and he has disconnected that led of the circuit so the other lights can operate.
my guess is then it was badly terminated in the beginning.
the sparky told my partner it should have been plastic and metal will always rust and we should replace the lot.
which is not what i want its a pure sandstone tower and it would look horrendous with conduit.
thanks once again

 

[Pete999]

thanks for the advice guys . yes it is wall mounted and it tripps when the lights are off . i had a sparky come round and he has disconnected that led of the circuit so the other lights can operate.
my guess is then it was badly terminated in the beginning.
the sparky told my partner it should have been plastic and metal will always rust and we should replace the lot.
which is not what i want its a pure sandstone tower and it would look horrendous with conduit.
thanks once again

Get a decent Electrician to do the damp test I posted earlier, and ask him if he can remake the faulty end, it/s not impossible to repair. Didn't know copper rusted though.

 

[roland1976]

cheers pete
the advice may have been mistranslated by the misses, but really didnt want to pull down all that dressing work to replace it with plastic.

 

[Pete999]

cheers pete
the advice may have been mistranslated by the misses, but really didnt want to pull down all that dressing work to replace it with plastic.

No probs Roland.