ECN Forum Forums General Topics of the Trade General Discussion Area Bad 240V butt-splice

Customer has a 240V, 3 phase, 3wire service to his shop. Phase A(black)= 208V to GRD, Phase B(red)= 0V to GRD, Phase C(blue)= 240V to GRD. When MAIN DISCO. is turned OFF(no load), Phase A(black) jumps up to 240V to GRD, like it should be. Turn MAIN back on(load applied), 208V to GRD again. Phase B & C stay same. Phase A has a crimped Butt-Splice in the meter can, and "sizzles" for a few seconds, when MAIN is turned back on. I had POCO disconnect power to shop until I could replace splice in morning. Anyone ever come across this before? Why would voltage drop under load? Also, not much experience with 240V, 3 wire, 3 phase. Phase "B" was grounded. Does that act as a neutral? POCO double checked their XFR, and verified their voltage was correct, 240V phase to phase. It is a 5 year old, underground service. No one has been trenching near service, but still not 100% sure the splice is the problem.