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Re: TDR for power line


 

I've used TDR to find fault on small JKT(telephone wire) to underground tech cable (10-3)?

The velocity can be anywhere between 50 to 90 % Make sure there is no remaining power connected to any of the wire and I would suggest that you put a known terminating load at the?cable end and make the same test without. This helped me find a lot of strange breaks in the security system cable. And in a oil refinery regulation system.?

Pierre
VE2PF

On Mon, Apr 7, 2025 at 11:38?PM Karl Shoemaker via <srg734=[email protected]> wrote:
Anyone have experience using a TDR to locate an underground fault for high voltage ?
There's a PUD in central Washing that can't appear to fix an outage for the past three weeks or so.
It's affecting several comm sites and one ski area. It's high up around 7,000 ASL with 20-foot drifts.? The road is derivable around the first or second week of July each season.?
?
I'm not sure if it's incompetence or lack of training but the concept seems simple enough to me; send a pulse down the line and watch for the return indicating something is wrong.?
There are several of these units on the market, on line.?
?
I also suspect it's not an exact science and requires lots of experience to be effective.?
If I were in the area I suppose I could hook up the (dead) line to a spark plug circuit (from an engine or whatever) and walk the mile line listening for anomalies with an AM radio.?
For now, one leasee is dragging large amounts of propane to keep one site alive.?
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Regards, Karl Shoemaker
To contact me, please visit SRG's web site at?
for the current email address.

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