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Power cuts and electric shocks
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G7PSK:
This morning we had a power outage while the wife was in the shower, the whole are went out. The strange thing is my wife got an electric shock as the power went out,the shower is a pumped type.
The power network engineers came round and tested the supply as I had reported the shock to UK power networks. the engineers told me the reason the power went out was due to a high voltage line coming loose in the wind and striking against the metal work of the sub station which is about twelve miles from the house. What I don't understand and neither did the power engineers is how or why the wife got the shock.
Our supply uses the company's earth which I assume is bonded right back to the sub station and beyond.
Did the high voltage line hitting the steel work send some power right along the earth/ground wires and so through the wife or is it down inductance between the live and earth/ground cables in the supply which is all overhead where I live.
mzzj:
If the "company earth" is not bonded to everything else in the house that is more or less expected.
In here it would be normal  to bond "company earth", house plumbing,  rebar(house foundation) and grounding electrodes to Potential equalization bar.
G7PSK:
Every thing is bonded, up until a couple of years ago we had our own earthing via the usual rod in the ground but one day when playing with the scope I realised we no longer had a very good earth so I called an electrician who moved the outgoing earth wire from the rod onto the company incoming earth. We have a pole just 30 meters from the house where our power comes from and at the base of that is a large earthing plate as well an earth line going back along the overheads.
engrguy42:
Hard to say for sure (especially since I'm only familiar with US, not UK), but when if the power line fell inside the substation, the substation has a big metallic ground grid mat in the earth underneath it. When the line falls on metal in the station it goes to the ground grid, but it has to go back to the source(s), where ever they might be. Probably there's a grounded transformer in the station where it fell, but there may also be other remote sources the current can flow back to. It can distribute itself in the earth and return to multiple remote sources far away.

Kinda surprising if it was 12 miles away, but I suppose it's possible there is another station that also has a grounding transformer near your house where some of the current flowed. Depending on the impedance of the ground around your house there may have been enough potential generated at your house (maybe the ground rod outside your house isn't connected very well to ground or something?).

Now if the power lines in your neighborhood have 4 wires (which include a dedicated ground wire), this is much less likely since the ground current will probably flow on those wires not in the earth.

If you want to do some detective work get on Google Earth and see if you can find a substation 12 miles away, and another one near your house  :D  And if you can zoom in to the one nearest your house and see the low voltage side of the transformer feeding the distribution system has 4 bushings, it's probably Y grounded and the current may have flowed back to that transformer.
 
Seems strange. Not good that you get a shock for something like that. Maybe have an electrician come and check your grounds in the house. A good ground in your house should limit any potentials like that. 
G7PSK:
There is another transformer station around three miles away that feeds power from a solar farm that is only a quarter mile away from out house into the grid. Our LV supply comes from a pole transformer that is only five poles away from us.
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