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Apparent crossed phase on power supply

Apparent crossed phase on power supply

Apparent crossed phase on power supply

(OP)
My electricity supply had a fault recently whereby I had 240V on the neutral and 0V on the live. All my appliances worked with no real signs of a problem, I checked the voltage against my house earth (connected to a ground spike.) My nextdoor neighbour experienced exackly the same symptoms, they are connected to the same phase as me. The only other property fed from thr local pole transformer is a wood yard which uses all 3 phases. The power company put the fault down to a high resistance earth at the pole transformer and a fault within some machinery in the wood yard.
I am struggling to understand how any fault other than a crossed phase could cause the symptoms I experienced.
Can anyone offer a plausible explanation other than a crossed phase?  

RE: Apparent crossed phase on power supply

First it's hard to cross a phase on a single phase service.
If one line shorted to ground at the wood yard, and there was a faulty or high impedance connection in the ground path from the fault to the transformer, the symptoms that you describe may be experienced.

 

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Apparent crossed phase on power supply

(OP)
When I said crossed phase what I meant was the live and neutral crossed over. The electricity company recently carried out some work on the pole transformer and the problems appear to have started around the same time.
I'm not quite sure how the fault you suggested would cause the symptoms I experienced. If the live was shorted to earth I would have lost power but I had 240V on my neutral and 0V on my live 9measured to my local earth (ground spike).
Any other ideas?

RE: Apparent crossed phase on power supply

Sounds like "neutral inversion", try Googling the same.

Regards,
Lyle
 

RE: Apparent crossed phase on power supply

I agree with waross it is difficult to cross the live with neutral from the distribution panel as live is through fuse and neutral is direct, but may be
 in a repaired-wrong repaired -branch could happened.
 

RE: Apparent crossed phase on power supply

The utility may have grounded the wrong terminal at the transformer, or crossed the conductors feeding residential loads.
However this is an international forum and grounding methods vary in different parts of the world. To read line voltage between the neutral and the earth in North America would indicate, among other things that the local connection between the neutral bus and the ground bus or between the ground bus and the ground electrode in the residential service had gone open. From the description of the problem and the service voltage of 240 to neutral I suspect that you are not in North America and different grounding methods are in use.
We may have to leave this one to Scotty and the boys "Over there".

Bill
--------------------
"Why not the best?"
Jimmy Carter

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