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drying out cables

13K views 42 replies 18 participants last post by  Big John 
Most conductors are rated for moisture. Problems arise when the ends aren't sealed properly and moisture enters between the insulation. How wet did it get, how old is it, what makes you think it's got a moisture issue? All relevant questions. 4160 is nothing to monkey with and is the reason why I asked why you were asking. If it's for a new installation I hope to hell there is someone around who knows this stuff.
 
butcher733 said:
I am spectating this at my current job. One of the cables isn't megging out and they want to rule out moisture. There was a fault that trashed the line side of a transformer and they are wanting to rule out moisture invasion in the cable. I don't see how this would solve anything though. Once a cable causes a fault it is trash IMHO.
Is it like a lead sheathed mv cable? Water inside a cable can be responsible for expediting the breakdown of already weak spots in the insulation. Drying a cable out doesn't always make things better though due to the impurities in the water that are left behind afterwards. I wouldn't think that water in a cable could produce a full blown fault but it's hard to say without knowing the type of cable and insulation in question.
 
Shock-Therapy said:
Im not grilling you, Im just interested in hearing more about the impurities left behind part....
Pure water is actually an insulator. But pure water (distilled) is not typically what we're talking about when it comes to water damage in a cable. Rain water is formed around dust and pollutants and ground water contains minerals and salts; all of this is still present after the water evaporates and however minimal the conductivity of the material it still can attribute to high resistance faults, especially in mv
 
8V71 said:
Is this going to be a problem? Going on 3 weeks and I don't know how much longer. There are 6 open ends like this that are not sealed and one is laying in the grass with all of this rain and snow that we have had. It's 15kv cable with 7.2k going through it but a few feet will be cut off before terminating.
I'd say that's their problem (poco). Right?
 
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