Author -Submitted By -
3 phase 480 bank
2 lineman were recently killed in california when a transfomer in a bank blew up cooking the lineman with the hot oil. they had replaced one pot on the outside of an overhead 480 bank. when they reenergized the bank the center pot failed. management said there was a small amount of arcing between the pri windings and the secondary windings. this created ascetalene gas that built up inside the tank. when the bank had load put on it the arc grew and ignited the gas and blew the shit out of everything. the troubleman who responded to the part lites call only guesed that the outside pot was bad they didnt test it therby setting up the crew who did the work. i guess the morale is dont always believe the testman. check for yourself even if it is more work. be safe.