First, thanks for all the excellent advice on this site.
While wiring an auxiliary heat strip to the 125A sub panel in my basement, I noticed that the sub panel does not have a grounding wire from the main panel. The main panel is 25 feet away in the basement. I would like to add the ground wire. The neutral bar on the sub panel is not bonded; I will add the grounding bar. I am in North Carolina. Here are my questions:
- Can I run the grounding wire on it's own zip tied to the whip carrying the hot and neutral wires (I cannot pull any wires through the whip as it is pre-made)?
- I'm planning on using #6 wire. Is that sufficient for the 125A sub panel?