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. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user