Sub panel ground

Am I correct that a sub distribution panel should have a grounding conductor connected to its ground bus (separate from the neutral bus) that is connected to the main panel’s neutral bus?

Sub panels require 3 conductors plus a ground. A separate ground bus, bonded to the panel and connected to the grounding conductor. Neutral bus is isolated from the panel case.

Thanks. That’s what I thought.

It’s not required to be connected to the neutral bus but if the feeder is originating at a service then the neutral and grounding bus may be one in the same.

John, is the dist. panel in a detached building?

No. The main and distribution panel are in the same building. What would be the difference?

How about this set-up? Sub in garage. Feed from breaker at top right at service panel. Home built in 1972.

What specific problems do you see?

If it’s a detached building, there are other issues to consider. Primarily whether or not a GES exists at the building. Separation of grounds and neutrals would be different depending on whether it’s a 3 wire or 4 wire feed to the building.

3 wire feeds to existing detached buildings

Grounding electrodes at outbuildings