201031-1106 EDT
jhardy13:
In your main panel there are normally two bus bars aside from the hots. One should be the EGC bar, and the other the neutral bar. These two bars are tied together by a very low impedance path, and must be. At the present moment I read 0.7 millivolts between my two bars with a Fluke 27 meter. But I also read 0.2 mV with the two meter leads just shorted together in that general region, and this one turn loop may not be seeing the same magnetic field as when I make the voltage drop measurement between the two bus bars. The basic point is that those two bars should be at essentially the same voltage.
When you turn off your main breaker in the main panel, then there should be no current flow from your power transformer back thru your neutral and EGC bus bars to the transformer center tap. You can check that you see no hot wire current. Assuming that hot wire current is zero, then look for what neutral or EGC wires have current flow. Look for and determine which wires show current flow. This current, if it exists, comes from somewhere else.
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