While trying to find out what is going on here , when measuring the mains voltage with a multimeter by connecting the red probe to the line and leaving the black (com) one laying in the floor after setting the multimeter to 600vac it reads 38v and when connecting the COM probe to to one of the holes in an extension board with a 3 meters cable NOT connected to anything just to make the probe longer the multimeter reads 103 volts
when the probe is taken of the floor the the voltage drops dramatically but doesn't reach zero
Electricity here is 240@50Hz and reads 244-246 when measuring it properly with same multimeter line to neutral and line to ground have the same value and neutral to ground is always zero.
I'm I doing something wrong?
What could be causing this?
Is this voltage ir what is causing it dangerous?
The house is on a cliff edge and high voltage power lines are 400 meters away without any obstruction
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USER249
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2Welcome to the worderful world of electric fields. – Andy aka Mar 01 '20 at 11:10
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2A low impedance meter won't suffer from such ghosting. – DKNguyen Mar 02 '20 at 15:45
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@DKNguyen I found it accidentally while powering a strip of LEDs. The meter was to confirm it. Take a look at the linked question. – USER249 Mar 02 '20 at 15:51
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Your DMM has a high enough input impedance such that the few pFs of stray capacity between your test lead and ground is a significant component. You'll notice your reading varies a lot as you change positions of leads and meter, which causes the stray capacity to change value.
You are not doing anything wrong.
It's no more dangerous than measuring mains in the normal way (which is not to say it's safe).

Neil_UK
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But what about this https://electronics.stackexchange.com/questions/483745/why-is-this-tv-led-strip-emitting-light-if-any-single-wire-alone-is-connected-to where is the current going to or coming from? my understanding to capacity is that it is dischargeable but this is not – USER249 Mar 01 '20 at 11:00
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What about that? A wall of text and no diagram. I'm not going to waste my time attempting to make sense of that. When you have 240v fields, 10s of pFs of stray capacitance, and meters with 10M input impedances, what do you expect? Get a circuit simulator, LTSpice is the standard amateur product, used by me, used by professionals as well, clunky and unfriendly interface, but good. Simmetrix has a free version, nice interface but only small circuits allowed in the free version. Put in some realistic stray Cs and meter impedances and see what you get. – Neil_UK Mar 01 '20 at 12:00
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Long story short : LED strip is emitting light if any driver output wire alone is connected to either one of its terminals but only near the floor. I will try to simulate it. – USER249 Mar 01 '20 at 16:47
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I have an old linux distro full of simulators and a proprietary student licensed one somewhere . I used these for flip-flops, gates and digital logic long time ago – USER249 Mar 01 '20 at 17:08