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electrical generation from unknown souce

electrical generation from unknown souce

(OP)
I have accidently discovered that my window screen on my front porch is conducting a\c voltage at 2.5 constantly.the screen is 4 feet by 10 feet long and is not grounded.i put a grounding rod aprox 4 feet deep and checked it again the voltage seems to be constant 24 hours a day.How can this be?Is it the metallugy of the zinc coated wire mesh causing this or is it resonance from the power lines near by? approx 100 feet away.hope to hear some opinions

RE: electrical generation from unknown souce

"...a\c voltage..."

At your local Line Frequency (50/60 Hz)?

Measured with a Hi-Z meter? I can sometimes get a volt or two on those just by holding the probes. Almost meaningless.

Adjust the meter to measure the AC current to ground. That's far more meaningful than the voltage into a Hi-Z meter.

RE: electrical generation from unknown souce

If you have long-wire antenna as sometimes used on a short-wave receiver, you can hook a small neon bulb between the antenna and ground and get it to glow. The gas in a neon bulb ionizes at about 40 volts. Although there is voltage, there is not much energy (voltage x current x time) to do any useful work. That is, unless you try it in an electrical storm, or get a direct hit by lightning. But even then, the energy is not in a form that is easy to capture and use.

There is always a lot of electrical potential around between insulated metal objects and ground arising from potential differences (AC or DC power), moving magnetic fields (electrical induction), charge difference (static), RF fields, chemical process (dissimilar metals), or even sunlight knocking electrons loose (photoelectric effect).

RE: electrical generation from unknown souce

It is more than likely 'receiving' an e or m field from your house wiring. You can test that by turning off your house. You will likely see the voltage drop significantly or totally.

Keith Cress
kcress - http://www.flaminsystems.com

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