> After a wind storm, appliances and lights in the house across
> the street were behaving very oddly.  Electric utility had so
> many repairs they were estimating 4-5 days before they could
> get to it.  The neighbors asked me to look at it.
>
> I was seeing 60 volts to 150 volts on various outlets in the
> house.  And it would vary depending on what lights and/or
> appliances were running.  I suspected a bad neutral.
>
<snip>

> I explained to the owners that they should fix the lack of a
> local ground on their breaker panel.  Not sure if they ever
> did so.
>
> Lee Jones

Of course such a local ground is not likely to correct this problem 
completely. The impedance of that ground is not likely to be low enough to 
avoid a significant switch of the neutral's voltage. Grounding at the 
utility pole and the residence is only intended to be sure that the neutral 
is at zero potential to ground, when no (or minimal) current is flowing in 
the grounding conductors. It is for this reason that the required conductor 
size for this grounding conductor is _much_ smaller than the service 
conductors. In fact, a situation where a significant neutral current were 
forced thru the grounding conductor might be unsafe in and of itself.

Bob Ammerman
RAm Systems


-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist