Cable Fail

[telectrix]

40m brand new 6mm 3core SWA all exposed, no visible damage. 238V at one end, bugger all at t'other. only good point is that customer supplied cable,so it's his problem getting it replaced. wondering if it's some cheap foreign stuff. anyone heard of bad SWA floating around?

 

[7029 dave]

That's a pain, oh well replace, end to end and IR test before new length gets layed.

 

[telectrix]

good thinking. forgot to mention that the cable has been working OK for several weeks. just failed the other day.

 

[Lucien Nunes]

So one or more cores probably have a mechanical joint in where the new roll of conductor was put on the machine, but they forgot to cut it out of the finished cable. I wonder how many of those are in service, I found a couple in the middle of a roll of flex recently revealed only by a slight bulge.

 

[driverman]

So one or more cores probably have a mechanical joint in where the new roll of conductor was put on the machine, but they forgot to cut it out of the finished cable. I wonder how many of those are in service, I found a couple in the middle of a roll of flex recently revealed only by a slight bulge.

a slight bulge gives a lot away! lol

 

[7029 dave]

Yes I had that with 100mt drum of 2.5 t&e once.

 

[telectrix]

hmm, interesting. in was beginning to doubt my sanity. first check was with a voltsick. then the approved tester came out. power at source, fine. t'other end was ziltch L-N and L-E, so must be the line conductor. as it's 3 core with a cpc conductor and the armour used, i though of pinching the cpc conductor and sleeving it as a temp measure, but decided against it as if 1 core has failed, then another 1 might. anyway, it was pi$$ing down and not easy to work with 1 hand holding up a brolly, so thought sod it. let him get a new cable.

 

[Lucien Nunes]

I'd give up on it too. All three cores might have joints, just happened to be the line that failed first. It's a very insidious failure, the insulation is half what it should be (or technically none from conductor to outside of a PVC sheathed cable) and the joint could have anywhere from zero to full rated capacity. It's nearly as evil as a JB full of wirenuts.

E2A would be interesting to see it when you pull it out, hopefully it has revealed itself by a bit of melting or something. Or I suppose as it's totally O/C you could find it with a capacitance meter.

 

[driverman]

hmm, interesting. in was beginning to doubt my sanity. first check was with a voltsick. then the approved tester came out. power at source, fine. t'other end was ziltch L-N and L-E, so must be the line conductor. as it's 3 core with a cpc conductor and the armour used, i though of pinching the cpc conductor and sleeving it as a temp measure, but decided against it as if 1 core has failed, then another 1 might. anyway, it was pi$$ing down and not easy to work with 1 hand holding up a brolly, so thought sod it. let him get a new cable.

Bet it wasn't installed in ducting!

 

[7029 dave]

Best to Tel, if its shagged.

 

[telectrix]

Bet it wasn't installed in ducting!

it's just laying on the ground awaiting to customer to dig a trench. ( it's a travellers site, so they have the wherewithall to do the groundworks.

 

[driverman]

it's just laying on the ground awaiting to customer to dig a trench. ( it's a travellers site, so they have the wherewithall to do the groundworks.

Could of been a lot worst then if already buried.

 

[LeeH]

it's a travellers site

The broken core probably happened when the fastened it to the back of a transit and pulled it out some poor sods factory down the road.

 

[telectrix]

haha. no, i can assure you he bought it, but the muppet at the wholesalers didn't tape the first coil, so it was a nightmare to unroll.

 

[guest119]

haha. no, i can assure you he bought it, but the muppet at the wholesalers didn't tape the first coil, so it was a nightmare to unroll.

CEF?

Boydy