[LAU] ground loop hell

Jan Depner eviltwin69 at cableone.net
Sun Feb 8 21:00:18 UTC 2015

On Sun, 2015-02-08 at 15:32 -0500, Gene Heskett wrote:
> On Sunday, February 08, 2015 02:53:28 PM Ralf Mardorf wrote:
> > On Sun, 8 Feb 2015 09:06:40 -0800 (PST), Len Ovens wrote:
> > >It appears we have power coming from two power entrances with two
> > >different earth grounds to the panels.
> > 
> > I experienced potential difference for the ground in old buildings
> > between two main sockets, less than 3 meters difference between those
> > sockets, both fed by the same power, coming from the same fuse and
> > connected to the same concrete-footing ground electrode.
> > 
> > Even if the power should come from two different sources, one building
> > should have one concrete-footing ground electrode for ground, so in
> > theory there shouldn't be a potential difference.
> > 
> > Buildings sometimes don't care about school books.
> Tisn't the building, its the idiot who did the wiring Ralf.  A distinct 
> possibility he was color blind or 20 years short of a journeyman card.  Or 
> both...
> I would, when something like that is found in the middle of a concert, stop 
> it, tell the promoter to refund everyines money, and to let you know when 
> the problem is fixed, you might save someones life, maybe your own
> ANY time I go into that sort of a situation where there are unknowns, I have 
> oner of those little $9.95 pocket pen sized beepers that you can stick its 
> insulated probe into a socket and tell in an instant if its wired per code.  
> If it beeps on what should be the static ground, or the neutral slot, the 
> show is off till its fixed.  And it is not open for discussion.  And I would 
> not be the least bit retgicent about calling any other groups you know about 
> and warning them.  It WILL get fixed when his popular groups tell him not 
> until its been fixed.
> That gizmo is for sale, in several flavors and colors in any home 
> center/lumber yard/electrical wholesale, for various prices but are all 
> pretty much identical inside.  The $9.95 veersion works as well as the 
> $19.95 version in my experience. And 6 or 7 years old, still running on the 
> original batteries.
> Sometimes you really do have to be an a$$hole about that sort of thing.

While I agree in principle, if you play in the New Orleans area you'll
starve.  I don't think there's a building in any of the old sections of
NO that is wired to code.  I've been zapped so many times that I'm
beginning to glow in the dark ;-)

> Cheers, Gene Heskett

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