160 volts on coax cable.

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Crash117 said:
When main power to the house is shut off at the main panel, which is on a pole 75 feet from the house, the coax still has 160 volts between the 2 cables and still has 38 volts to ground.
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Simple. THEIR OSP (cable and strand) IS HOT! They need to find the problem and fix it before one of their guys gets killed!

Why are these guys so stupid to always blame something like this on their customer??

-Hal
 
How about a new drop? Only think I can think of is the CATV distribution equipment has energized the house drop somehow, but that doesn't explain 160V and doesn't explain it energized while disconnected.
 
I've had shielded control cable laying on the ground beneath power lines that would charge up in just a few seconds. I never checked voltage but the discharge to ground was both quite visible and loud. I think the primary was in the 30Kv range. Ground or earth one end of the shield and see what happens
 
tthh said:
Only think I can think of is the CATV distribution equipment has energized the house drop somehow, but that doesn't explain 160V and doesn't explain it energized while disconnected.
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That's exactly what's happening. The 160V because of leakage from the primary through a damp pole. When I worked for a cable company we were "encouraged" to jab a pole with a leakage tester before climbing. Every once and a while we would see a pole with a note on it that said "HOT POLE" and we would know to keep away.

-Hal
 
Crash117 said:
While both sides are disconnected, this air drop still generates 160 volts.
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As measured how? Relative to what? Are you saying that the inner and outer conductors have a 160V potential between them? If so, what are the voltages on those conductors referenced to a reliable ground?

Voltage is not absolute; when you say a conductor has a voltage on it, that doesn't mean anything if you don't say relative to what.
 
The voltage is measured between the utility drop to house cable at 160 volts, and also between ground and neutral at the closest panel to the cable utility drop which is about 15’ apart. This panel is 1 of 2 sub panels fed from a pole mounted main that is 75’ away from the house. All voltage test were performed with both sub panels turned off at the pole mounted main. Both 200 amp mains in this panel are off. This was verify by testing for voltage at each panel. The voltage is on the utility drop between the house and where it leaves utility pole via aerial feed to the house. Both ends of this aerial feed are disconnected but voltage is still present. Has to be induced due to proximity of coax lines on the pole to high voltage lines installed on same pole at about 10’ of separation between them. The voltage is not present in the house coax when it is disconnected from aerial drop.
 
It was not connected to ground when I arrived but I used a coax grounding block during testing and it made no difference on the voltage. 160 to ground with or without coax grounding block. The voltage is on the coax inner conductor. I used both the ground wire present in the utility provided demarc box and also extended a ground from the nearby sub panel which has a # 4 solid ufer ground in it. This panel has separate ground and neutral bars which are not bonded. The problem voltage reads 160 from coax to ground and coax to neutral. This testing was done with sub panel shut off.
 
Crash117 said:
Both ends of this aerial feed are disconnected but voltage is still present.
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Are you saying that the drop is disconnected at the pole?? Drop is just hanging in the air both ends disconnected and you are getting 160V from the center conductor to ground??

Forget the center conductor, what about the connector to ground?

Keep in mind- messengered drop cable with the pole end of the messenger bonded to the strand, cut off at the house. That is still connected.

What meter are you using?

-Hal
 
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