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remember those prods we used to get fishing worms to come out of the ground? lol

I have to tell this story.

About two years ago we were called to a large aparment complex. it seemed that when any one would come into contact with any thing that was grounded to the service egc the would recive a shock when we mesured it to a ground rod that we installed about 25' away it was about 56volts but it would vary in perportion to how much load was being pulled on the main service (800 amp) even the transformer pad was hot. we then called the power company and at first they tryed to tell us its on our side of the service but after a call to the companys EE they did some testing and found out the concentric neutral didn't have any current on it. so they pulled up the primary feed and found that the neutral had burned off after they replaced it every thing was fine then the next summer we got called again for the same thing. the power company came back out and when they check the neutral it didn't have any current on it but when the lineman tuched the cable it came back up he found that the preveous lineman had just cut the old neutral off about a foot from where it was bonded to the main neutral, and connected the new run to the end of it. the origenel connection was the resion the first cable burned off. but when the neutral was lost the transformer was pulling power through the grounding system which included the main water pipe which is electricly soiled between two services on another building not far away.we had about 6 amps on the neutral coming from the transformer seconedary. even though the transformer has its own ground rod.and there was two ground rods at the service on the building. then a one ott wire to the water main and the reverse at the other buildings. how could there be this much voltage drop across these grounds? the water pipe was amp probed at the other buildings to make sure it was continous.

Talked to a linesman today about this....

He said that they loose primary noodels all the time, sometimes with no customer complaints at all!

makes ya think.....

Great graphic Steve!