H/O of house I wired called to report flickering lights. Said I'd get by soon; in the mean time he called again. He had removed the panel cover and found 15a CH-BR had 'melted down'.(guess the cover felt hot)and had damaged adjacent bkr. He replaced them and all seems fine. His 'friend sparky' looked at it after and must have amped the circuit and pronounced the load OK. ? is, is this common? how could it tolerate such heat and not trip? what condition(s) on the circuit could cause this?
