Last summer i had an RTAC 200 comp2 phase reversal alarm. We know there was not a true phase reversal because the chiller is 4.5 years old, other circuit runs fine, all high voltage was triple checked. Comp motor megs good, CT's check good starter module was replaced with a new one and the cross line starter was replaced. Still locks out on in about .3 seconds. Trane tech support had me remove the suction line from compressor and turn the compressor by hand (Yes you can turn a 100 ton Trane screw compressor with you bear hand) to determine if we had locked rotor, which we did not.. At this point Trane tech support said we don't what is wrong, call your local Trane dealer. Working with my local Trane dealer we decided to connect the working comp 1 to the comp 2 starter, we started the comp 1 and ran it about 45 t0 60 seconds. Compressor 2 was replaced and the problem was solved. Now at a building next door (same campus about 300 yards away) i have a RTAC 250 with the same symptoms. Has anyone had this type of problem, any in put would be great.