I just had my inspection today for my 400A service. Passed good enough to get the stickers applied to the meter base and panel, but the inspector commented that my bonding bushings should have a locknut under them. I do have a locknut on the outside of the box, just not on the inside sandwiched between the box and the bushing. I've tried to do this in the past, but rarely are the conduit threads long enough to get that bonding bushing on far enough for my satisfaction (so the set screw fully hits threads).
So are service bonding bushings (the metal ones with a lug, set screw, and non metallic ring to protect the wires) considered inadequate to hold conduits in place? How many threads are required to engage the conduit?
I don't think the inspector is going to make me change that, it seemed more like a comment. He seemed to buy my reasoning of not enough thread. What do you guys think?