I went to a customers farm today for a power quality ticket. He has 8,2 lamp high output flor. fixtures on a 20 amp breaker,panel and lights are one year old. The 20 amp breaker trips about once a month the breaker has only 13 amps of load. All the wire is in conduit and armoured cable. Would it be possible it is just a bad breaker? I told him that would be a good place to start. It is a square d panel. Is there a special breakers for this type load?