I pull the
neutral,
ground takes its place as an alternate path
The
ground path should a no
point be connected to the
neutral (except at the service entrance) so it would not become an alternate
neutral path. As "Allthings" stated above, the load imbalance would quickly take out the
leg with the lowest load.
I think it was in Allentown PA in the mid 80's, but I watched as REM lost a lot of their
system when the
bolt holding their
neutral lug snapped mid show. Guess the
house electrician torqued it down a
bit too much. Lost neutrals are not a pretty sight.
EDIT:
As for where the over-voltage comes from, imagine you have a single
phase 120-0-120 feed. (two hots and a
neutral) From one hot to
neutral, you have a 200
ohm load, from the other hot to
neutral you have a 40
ohm load. As long as both loads see
neutral, both loads will have 120 volts across them. Now,
disconnect the
neutral. You now have a 240
ohm load on 240 volts, or about a volt per
ohm. If at this
point you looked at the junction, you would find 40 volts dropping across the 40
ohm load, and 200 volts dropping across the 200
ohm load. In other words, what was the
neutral point has shifted 80 volts producing an under-voltage on the 40
ohm load and an over-voltage on the 200
ohm load. I hope this helps.
Remember, ohms = volts / amps, so the heavier the load the lower the ohmage.