Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!elroy.jpl.nasa.gov!ncar!gatech!hubcap!rbrink
From: rbrink@hubcap.clemson.edu (Rick Brink)
Newsgroups: sci.electronics
Subject: Re: Stray Voltage? on 60 Minutes
Message-ID: <1991Apr15.172627.13060@hubcap.clemson.edu>
Date: 15 Apr 91 17:26:27 GMT
References: <746@newave.UUCP>
Distribution: usa
Organization: Clemson University
Lines: 22

From article <746@newave.UUCP>, by john@newave.UUCP (John A. Weeks III):
> In article <3853@uc.msc.umn.edu> dwm@msc.edu (Don Mears) writes:
>> Can someone explain what they were talking about on 60 minutes on 4/7
>> in the piece on stray voltage from old power lines that caused
>> dead and deformed animals, and shocks to people?  These did not look like
>> high voltage power lines, just  normal ~10kv distribution lines. 

You don't have to go to the cow barn to find stray voltage.  I did some
electrical repair work in a vegtable packing house here in South Carolina.
While installing some new equipment, I got several good "bites" from the 
frame of a conveyer.  I started checking around....I found the closest true
ground in the system, at the pole outside!  None of the equipment was frame
grounded or cross grounded. The whole system relied on the neutral (in the
single phase circuits) nothing in the 3phase circuits.  It seems the the
whole system was homegrown, and had origionally been grounded to the building
rebar.  But someone had knocked the ground strap loose with a forklift
sometime ago...  Only pure luck saved lives there.  With all that running 
water, and the overloaded motor circuits poping breakers, it was a 
disaster waiting to happen.  The worst part of it, was the additions done
to the origional circuits by several licensed contractors, without ever
checking the safty of the system.  I was just repairing some small gearmotors
next to the line afterhours when I discovered it.