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Deadly problem with house wiring
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Monkeh:

--- Quote from: MarcusFunt on April 06, 2022, 06:57:02 pm ---Do you rekkon something is wrong with the pc supply?

--- End quote ---

Not likely.
tooki:
This question gets asked every year or so: “I feel (and/or can measure) a tingly voltage. What’s wrong?” and the answer remains the same: it’s the class-Y interference suppression caps in a switching power supply doing their job. If it can be felt or measured, it’s not grounded, be it because the power supply doesn’t have a ground, or because the outlet in use is not grounded.
Berni:
This is quite a common issue with non eathed appliances, nothing to worry about.

Whenever your device has just a mains plug with only 2 connections that means it is not earthed so the current from the Y capacitors in the PSU can't flow back to ground. This can be made even worse when you plug together multiple equipment with no ground as the currents can add up to something that can give a slight shock.

The issue goes away as soon as you plug in a earthed device, such as for example connecting a external monitor with a earthed plug into the laptop. That device pulls the ground potential down to earth potential.

It is also possible to buy a different laptop power adapter that does have earth (typically if they have a 3 pin power connector they connect ground to earth inside).

The only reason you would call an electrician over this is if you have devices with 3 pin power plugs (plugged directly into a wall) that still give you shocks. In that case you might have the earth wire interrupted in your house wiring. That is indeed VERY dangerous and should be fixed.
langwadt:

--- Quote from: MarcusFunt on April 06, 2022, 05:53:15 pm ---I did the same tests again with a 820kohm to simulate a human body. I got 7 volt om the solderimg iron(enough to feel on my leg with a antistatic strap on ).  On the Charger i got 1 volt with my body as gnd ref. I got 115 volt (yes. not a mistake) through the resistor on the mic.i got the same 115 across a 410kohm with a 4nf cap on.
I suspect that the same problem is happening in out Kitchen because we can feel a small elektrick shock when we touch the body of the microwave(gnd is Stone tiles)

--- End quote ---

the microwave probably has a shuko plug so it isn't grounded (as it probably should be) get a shuko to 3 pin danish plug adapter and plug it into a grounded outlet
coppercone2:
https://www.grainger.com/know-how/safety/electrical-hazard-safety/advanced-electrical-maintenance/kh-ghost-voltages

https://www.fluke.com/en-us/learn/blog/digital-multimeters/dual-impedance-digital-multimeters

To a novice at probing, this is useful.

You might want a old 100K input impedance meter, if you don't want to buy a fluke for low-z, but I recommend it. Just be sure to verify the low-z mode agrees with high z mode on a stiff source once in a while. If you think about it, the signal should be current limited. This is good to know, but high Z measurements are also good to know about (i.e. it might be associated with the risk of unpleasant tactile shocks).

You could do noise related modifications to equipment possibly to reduce this leakage in some things, but its quite advanced work (you still need to obey FCC and other government agency regulations on earth).
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