Pyro Cable Tripping RCD

[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

 

[vjsmarwick]

why are you using a makeshift extension lead ? your tester should be enough to test the cables not energizing a known faulty cable !!!!

 

[Silly Sausage]

Have you isolated/completely disconnected each length at both ends and IR tested each one separately?

 

[GLENNSPARK]

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

i`v told you how to dry it already.....
drive the damp out with a heat gun...

 

[sl1210]

yep and once i dry it out. who's to say it wont happen again in a week or two???

 

[Silly Sausage]

You make a proper repair to the electrics for starters, then if there's a water problem, you or someone else locates the source and get that dealt with. It's really not that difficult!

 

[Knobhead]

The pyro's been there for years, why should it develop several faults all at the same time.

I think it's time you looked at your testing method.

 

[UNG]

yep and once i dry it out. who's to say it wont happen again in a week or two???

I'm sorry but you are just showing a total lack of knowledge of the cable system you are working on here

 

[Engineer54]

Why are you not using your made for purpose test equipment to trace any potential faults on this circuit??

Well i have to say i'm very dubious that 4 separate legs of a MICC cable run suddenly go down together, all with suspected damp ingress!! As for replacing those legs with FP200, words escape me... lol!!

 

[Sparkii]

HaHa i can see megger bring one of those out, a plug with a bit connector block on the end! classic

 

[ackbarthestar]

Its very rare, I've never known it, for Pyro to go down all at once like the OP has suggested, unless a disgruntled member of the congregation has 'spiked' it along its route.

Have you checked the physical condition of the actual cable, rather than the pots ?
If moisture has got in it will most likely be at the point of termination .
Have you checked the quality of the sfcu/skts. M/C outlets often become corroded and can fail because of the moisture.

Having said that, unsheathed pyro is not difficult to heat and repot, although only having made one off at college, you'll have fun on your first one......