This all happened today.

I turned on my power switch to which my 3 monitors and 1 PC are connected via extension but nothing turned on. Wondering whats the reason i started my diagnosis on the switch. Reading noted:

Live - Neutral == 220V (reading were taken on naked wire)

Live-Neutral about 200V (reading taken on outlets of the power switch(On state))

Live-Neutral about 190 (reading taken on extension outlet)

Live-Ground ( about 150V) Netural-Ground (about 65V) (Not even near ideal but it's common on every switch of my home and everything is working fine)

Live-Ground (about 150). when switch turned on with no load, it went straight 70's.

First, it thought maybe resistance of LED of switch is cause of this so got new one and drop is way less but same when load is connected on the extension it doesn't turn on.

Last diagnosis: I connected defected monitor as a load to naked wires directly. Voltage difference of Live-Netural went from 220 to under 100.

Source wires are my home embedded ones. what can be the problem. This is literally the only switch in-home working abnormally. Breakers in our home are roomwise and rest of the room is working normal...

The reason i use this switch is because of earth wire availability on this one which is crucial for my system with ESD.

  • Your neutral is not grounded properly or not grounded at all. Technically it is not a ground, it is Protective Earth. Dangerous.
    – user263983
    Commented Jul 28, 2021 at 20:41
  • I think it's provider's fault or generator setting because i had 0V on neutral today and 227V L-N.
    – Divine
    Commented Jul 29, 2021 at 18:42
  • For me your electrical network looks like a mess. Invite professional to exam it.
    – user263983
    Commented Jul 30, 2021 at 1:27

1 Answer 1


I am assuming this worked earlier and the extension outlet is part of the structure not an extension cord. That sounds possibly like a fire hazard depending where the fault is. This will probably be difficult to find. You have a loose or bad connections somewhere. Connect a tungsten lamp (visual indicator and cheaper than monitors) instead of the monitor, a few hundred watts would be good. Then with your volt meter follow the wire back to the breaker box. Every time it passes through a box you may want to open it and check. Before opening it have somebody watch the lamp and bang on it rather roughly and see if the light flickers, if so you are close. If the voltage drops by more than a few volts between two boxes more than likely you missed one. Be sure you didn't. In that case I would suspect one of two problems, a hidden junction somewhere between or a bad wire(highly unlikely). At this point it would be best to get a professional.

  • To clarify, when you say "Bang on it" you mean the box and not the lamp, correct?
    – Duston
    Commented Jul 29, 2021 at 13:34
  • That is correct at each one as you trace it back. It is not a very scientific answer but sometimes it does work as it will vibrate the lose connection.
    – Gil
    Commented Jul 29, 2021 at 18:52
  • Extension was an extension cord. I switched my system on another socket today and took earth from the previous outlet to common out as the current one only had live and neutral wires. Things your saying like match wires back to board is hectic and kinda difficult because first, you have to identify the room's breaker then trace back-related wires which is in another deep layer because the house is about 30 years old.I left circuit open (disconnected from the outlet) only using earth wire from it.
    – Divine
    Commented Jul 29, 2021 at 18:52
  • I'll try your method on vacation.
    – Divine
    Commented Jul 29, 2021 at 18:57
  • The best advice I can give you is to hire a professional. It sounds like wires are coming from several places, that is dangerous.
    – Gil
    Commented Jul 29, 2021 at 18:58

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