I have not tested the transformers in my system but I would be very interested in the result of your inquiry. Please keep us posted.
Gmc, equal voltages between ground and neutral and hot? Are you certain that the IsoClean is wired correctly. Would this not cause the circuit breaker to trip? Oh, I keep forgeting that you are talking about the filter box. I no longer have the IsoClean filter box, but on another filter box I get only 2.9 volts from hot to ground and 0 from neutral to ground.
Please post when you hear back from IsoClean.