The "ground" at the rig is higher by the voltage drop on the RETURN = line, just as the "juice" at the rig is lower by the voltage drop on the = SUPPLY line. Their difference is double the drop on either. Hail Kirkoff! Dan / WG4S / K2 #2456 on 16 Guage wire (WAY Overkill). <snip> Huh???? Doug W6JD <snip>