I was wondering about the most effective residential service grounding method. Many use the domestic water piping (assume no plastic pipe/fittings in the lines). My concern with a copper piping system used as a ground involves possible electrolysis and slow damage to the pipe itself and the sweat joints. I have measured a small potential difference between the power company neutral and the piping ground. Could this small potential be a cause of electrolysis?
It seems the safest way to a ground residential system would be using a ground rod. Is there an effectiveness difference between the two methods? Any thoughts welcomed.
