Can you stand one more question about installing a sub panel?
I have installed a 100A sub panel in the stud bay adjacent to the 200A main panel in my garage; they are both Square D Homeline panels. I put a 100A breaker in the main panel and ran #2 wire from the breaker to the 100A breaker in the sub panel. I also ran one #2 from the ground/neutral feed in the main panel to the neutral bus in the sub panel.
I now understand that I need to add a separate ground wire from the main panel to the sub panel and that the neutrals and grounds should not be bonded in the sub panel. I'm also assuming that I'll need to buy an additonal bus bar and add it to the sub panel and use it to connect all of the ground wires. (Yes??)
I think I'm okay so far, but need advice on where to attach the separate ground wire in the main panel. Do the ground and neutral wires going to the sub panel both connect to the neutral/ground feed -- from the meter -- in the main panel?
I saw in other posts on this subject -- here and in other forums -- that if the sub panel is of a certain distance from the main panel that you have to install a separate ground rod or use a water pipe, etc., near the sub panel and run the ground to that. Since my sub panel is within inches of the main panel I think I'm okay running the ground from the sub back to the main panel. (Yes??)
Regarding the ground wire from the main to the sub panel, I have enough of the #2 wire to use for the additional ground, but wonder if I can get two #2s under the binding screws at either end. Thoughts on this??
If someone can help me understand where to terminate the grounds and neutrals in both panels, and comment on the issue of using #2 for the ground and whether it will fit under the binding screws at both ends, I would be most appreciative.
Finally, the whole reason I'm doing this is I want to install a 240V heater in my bathroom, plus I intend to finish out some attic space above the garage as living space, so I'll need more room for the additional circuits and the main panel is full.
I plan to use a GFCI breaker in the sub panel to feed the heater. That all looks pretty straight forward, but if there are "gotchas" that I should look out for I'm open to input.
Also, any other comments on the whole job are welcome.