I learned on one of these and it reminds me of:<p><a href="http://www.transmission-line.net/2011/07/zipses-law-and-its-dangers-in-grounding.html" rel="nofollow">http://www.transmission-line.net/2011/07/zipses-law-and-its-...</a><p>Zipse’ Law prohibits multi-ground systems: “In order to have and maintain a safe electrical installation: All continuous flowing current shall be contained within an insulated conductor or if a bare conductor, the conductor shall be installed on insulators, insulated from earth, except at one place within the system and only one place can the neutral be connected to earth.”