On 8/26/2015 8:19 AM, Paul Koning wrote: > > I heard of this sort of thing happening to the DEC building at Marlboro. > Supposedly it had two mains entrances, served from different power lines (and > different companies? Seems odd). One of the machine rooms had feeds from > both ends, and one particular system was fed from both. What happened is > that the "grounds" were offset enough, and with enough of a current supply, > that the ground strap that's supposed to connect the row of RP06 drives > melted. > > This sort of thing is a major electric code violation: you can certainly have > multiple services, but all the grounds are required to be connected by > substantial wire; you're not allowed to stick ground rods in at multiple > places and leave it at that. (The same goes for lightning rods.) > > paul >
Quite possibly two different phases, and if so, the would be 90 degrees out of phase with each other. JRJ
