In preparation for the final connection of my whole house generator, I’ve taken a look in my main panel with the objective of determining how I will go about un-bonding the ground and neutral busses.

The simple question is this: when the ground and neutral busses have been successfully un-bonded, should there be continuity between the neutral and buss bars? I thought not but here is what I found:

There is nothing but bare copper on the two ground buss bars and nothing but white on the three neutral bars. I begin by removing the bonding screw, still have continuity. I have three sub panels (pool, spa, shed) that I have wired up (4-wire, separate neutral/ground) but just in case I lifted these neutrals, still have continuity. So, at this point, I’m thinking I have a neutral/ground connection somewhere in the system (assuming my assumption is correct). I go outside, pull the meter come back in and lift the three neutral buss bars off the main neutral buss, still have continuity. I now go back outside and find that neutral is bonded to ground in the meter panel. I now lift the neutral lead from the meter box, return inside and find no continuity between the main neutral buss and ground. Good. So before I reassemble, I decide to test continuity between each of the three lifted neutral buss bars and ground. I find continuity between all three (actually 20-30 ohms).

I was going to take the time to lift each neutral from each neutral buss and test for continuity on each, but I thought I should ask you guys first. My thought was that for each piece of electrical equipment serviced, the neutral and ground would be distinct, but that doesn’t seem to be the case. Should I begin to trace down each specific circuit and see where the ‘problem’ lies? I know that the inspector wants to see the bonding occur in the yet to be installed transfer switch and I’m concerned that I’ll get dinged because of the continuity between the ground and neutral busses.

Neutral to ground occurs nearly EVERYWHERE. Here is an example. A non-polorized plug attached to a TV attached to cable. Guess what? There is neutral to ground connection.

Any watch yourself, you can get ZAPPED! And so can your electronic equipment if there is no neutral ground bond.

The existence of another ground neutral bond is easily checked with a clamp on meter designed to measure very low ground currents.