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Posted By: Trumpy Do You Pre-Test? - 04/23/04 10:45 AM
This question only came about after a really bad day, today Fault-finding a 400V 3 Core + Neutral Screened Cable, laid the other day.
A guy that I do quite a bit of work for asked me if he could lay his own cable, if I stipulated the cable and the installation methods.
No worries I said, he rang me later to look at the cable before it was finally buried and I had no problems with it.
In hind-sight, I should have Meggered the darn thing!. [Linked Image]
Went to hook up the cable (feeding a 3-phase pump) and tested the cable, I had a Dead-short over all 3 wires and to the Screening.
I eventually located the short to a section of cable that was buried .
I put a Tone Beacon down the cable and found the Fault, and dug up the damaged section, only to find a nasty piece of cable,that seemed a wee bit thinner than the rest of the cable.
I never had my D-cam, so I have no evidence of this.
It was just like it had been stretched during manufacture, in one place.
OK, so do you guys, pre-test cables, on the drum, before you install it?. [Linked Image]
Posted By: pauluk Re: Do You Pre-Test? - 04/23/04 11:14 PM
I don't think I've ever pre-tested on the reel, although I have meggered out a cable after laying but before terminating the ends.

Maybe the guy crushed it during the install and either didn't realize, or didn't think it was important.
Posted By: twh Re: Do You Pre-Test? - 04/25/04 04:27 AM
I only test if something looks wrong. The cable is tested on the reel before it leaves the factory. At least, it was at the place I visited. It sounds like a good idea, especially with a large cable or long run that would be difficult to roll up. I should start doing it.

I'm impressed that you got a fault locater to work. It must be a skill that I'm lacking.
Posted By: Trumpy Re: Do You Pre-Test? - 04/25/04 10:55 AM
twh,
Welcome to the Forum mate!. [Linked Image]
Pleased to have your input here!
Off the Drum, I would not normally test, but this was a wake up call and a half.
Won't be doing that a second time. [Linked Image]
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