I was thinking the lines of a PoCo problem myself. The #2 feeding the sub is about 30 to 35 feet from the 200 Amp main panel which is a back to back service having 4/0 Alum. to the main breaker. The sub panel is about 10 to 15 feet from the instant hot, containing 4 30 amp double pole breakers with #10 THWN CU stranded to each element. The PoCo transformer is pole mounted with their feed being underground down the pole running for about 150+ feet. It could very well be that their supply wire is 2/0 URD.
[This message has been edited by C.Urch (edited 04-17-2002).]
