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Urgent Help - Electrical Power Problems

Urgent Help - Electrical Power Problems

Urgent Help - Electrical Power Problems

(OP)
This is the situation on several sockets in a building.
(A)
Live-Neutral on some sockets     = 206V
Live-Earth on some sockets     = 130V
Neutral-Earth on some sockets    = 75V

Some others have this
(B)
Live-Neutral on some sockets     = 224V
Live-Earth on some sockets     = 224V
Neutral-Earth on some sockets    = 0V

and a third has these
(C)
Live-Neutral on some sockets     = 213V
Live-Earth on some sockets     = 213V
Neutral-Earth on some sockets    = 0V

When I test the above at the distribution panel, I do not get the (A) condition. (A) condition only occurs at some sockets in the building!

1. HOW DO I CORRECT THIS?

Also I noticed that Neutral-Earth voltage of about 2V even when all electrical source is disconnected at the distribution panel.
2. Can this voltage be coming from the EARTH?
3. Can multiple earthing create a problem? e.g. Generator earthed, VSAT dish earthed, telephone earthed in 2 places,etc?

RE: Urgent Help - Electrical Power Problems

I would suspect that you have a disconnected or burnt neutral conductor on a multiwire branch circuit or the neutral conductor coming from the utility somehow got severed.

RE: Urgent Help - Electrical Power Problems

 
GOTWW has a good point.  Consider that in the (A) case, line-to-ground faults nay not be able to operate an upstream overcurrent device, creating other hazards.
   

RE: Urgent Help - Electrical Power Problems

For (A) case, sum of (130V + 75V) is 205V, which is same as Live-Neutral.  I suspect there was a fault (Neutral shorted to Earth wire) somewhere in the circuit and it had frequently tripped the RCD, then someone tried to avoid the trips by disconnecting the earth wire near to the distribution board.

I make the above suggestion because I had seen some "smart" people (non-electrical) trying to do something to avoid "nuisance trip".

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