Pyro Cable Tripping RCD

[sl1210]

Went to a job in a church hall today where one of the power circuits was tripping the rcd. There seems to be 4 bad legs of pyro in the circuit, as I get a dead short in my IR tests between line/neutral, line/earth.

Is it common for pyro cable to do this after a certain time, or could a fault have caused this?

I have disconnected all the faulty legs and managed to keep the rcd on with only one socket working. I'm going to have to re-link the damaged pyro with new cable.

Was wandering if I could use 2.5mm FP cable clipped direct, or whether because its a church hall i would need to run it in plastic conduit???

Cheers

 

[richy3333]

Why can't god make it better, it's his house?

 

[Silly Sausage]

Why can't god make it better, it's his house?

If it's Catholic, he'll want paying.

 

[GLENNSPARK]

confession time...
i peed into the pyro......when he wern`t lookin....

 

[Stroppy]

Dirty boy! Anyway 'He' sees everything.

 

[UNG]

I find it strange that four lengths of Pyro have gone down at the same time and can't help but feel the OP's lack of any useful experience with Pyro is not helping in identifying the problem or it's cause

It would be interesting to have sight of the last PIR / EICR to check the IR values of the circuit in question when it was last tested

 

[Silly Sausage]

I suspect lack of experience here, something he said earlier (hate criticising people I don't know)
Deeper testing required. Pictures would be good too.

 

[nikmet]

im thinking a possible load still connected and out of sight maybe, have you got a clear view of the entire pyro run or does it disappear into a wall, roof void, floor etc?

 

[ayjay]

oh, god is my father, pyro my son
thou art be with me, and every-one--
fp200, a bodge up to make, but boys have to make-- a holy mistake?

 

[Guest55]

im thinking a possible load still connected and out of sight maybe, have you got a clear view of the entire pyro run or does it disappear into a wall, roof void, floor etc?

a connected load would almost certainly show a poor L-N reading rather than a N-E short.

 

[Guest55]

church walls are mostly solid rather than cavity and as such are virtually permanently damp , so i'd go with water ingress at a possibly hidden j.b's / counduit boxes somewhere.

 

[Silly Sausage]

I was best man the other week in church and all the walls and micc looked perfectly fine to me.

 

[vjsmarwick]

i would have thought dampness at first read too but if the ends were made of correctly and have been there for years i would suspect either there has been someone that knows nothing about pyro turning the pot after its been made off or some other damage else where but find it very strange that 4 cables go all at one time.

 

[sl1210]

hi guys. like i said i can trace the pyro from the first socket to a metal conduit box on the other side of the wall of the consumer unit, where it then joins singles in a connector and then to the consumer unit.

so my readings cant be because of a connected load as i had separated all the cables.

like i said as soon as i plugged my make shift extension lead into the suspect pyro's they trip instantly. only a couple held.

 

[GLENNSPARK]

it`l be damp will that...

 

[sl1210]

when i disconnect the piro from the connector block with singles going to the consumer unit the rcd holds. as soon as i touch the piro line to the single line. rcd trips.

i'm sure its damp too but really wouldn't know how to dry it. and i'm sure it could happen again anyways