catv coax voltage


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Old 04-18-14, 09:19 AM
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catv coax voltage

I was installing some coax for CATV for my parents this morning.

With the coax connected to cable box and tv but not to the splitter (line) I was getting 55VAC to ground!! With a digital multimeter.

Then I borrowed the neighbors low impendence fluke brand multimeter and it was only registering less than 1VAC.

neighbor said something about ghost voltage but in order to not look like an idiot I just agreed... what is he referring to?
 
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Old 04-18-14, 09:48 AM
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Ghost voltage or actually induced voltage occurs when you have a live wire running parallel to a dead wire. A sensitive meter will show a random voltage on the dead wire that is actually induced on it from the live wire.
 
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Old 04-18-14, 10:24 AM
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the "ghost" voltage and the minisicule voltage with the low impendance meter both disappeared when the surge strip with cable box and tv was turned off. So the induced voltage as you describe came from the box.

So what would be normal voltage ranges for a coax plugged into a cable box?
 
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Old 04-18-14, 10:28 AM
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There is no normal voltage. If you use an actual electricians voltage tester you won't measure anything.
 
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Old 04-18-14, 10:37 AM
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Old 04-18-14, 11:55 AM
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thx for posting the link, that explains it in simple terms for sure. Happy easter all.
 
 

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