So I've lived in this house for 8 years. One part of the house has wiring and a sub panel from the 50's. I had an electrical guy put in a new 200amp main service a year or so after we bought the home. Because of a recent problem at work I checked the old subpanel and both the Neutral and the ground wire from the main panel go directly to three connected bars. There was continuity between all three bars. I was told by the electrical contractor at work that this was not a good idea and that I could be causing damage to anyelectrical device on that sub panel. You want the Neutral and the ground to be connected in the main panel (which it is) and not in the sub panels. Come to think of it we have had a lot of problems. Some of the old Fiber covered wiring does not have a bare ground wire so the black leg goes to the hot breaker and the white wire goes to this common ground/Neutral bar. Even the newer wiring had both the neutral wire and the ground wire going to the same bar. So I went down to Depot and bought a bar to use as a neutral bar, but I ended up being able to isolate one of the three bars so that there was no continuety between the two ground bars and the third bar I would use for my neutral. I pulled the Neutral feed from the main panel and attached it to this isolated bar. I then pulled all the white wires from circuits that had a hot/ground/Neutral and attached them to the new bar. I left all the really old white wires that come off the Black/white no Neutral circuits on the ground bar. Have I done what needs to be done? When I now check continuity between the two ground bars and the new isolated neutral bar, I get pulsating continuety... on...off...on...off. Is that correct? I love and hate electricity.