A new type of twist-on splicing connector for use with aluminumand copper wire combinations was utilized to reconnect wire terminationsin a group of residential apartment units. The connector differs fromconventional twist-on connectors in that it is pre-filled with acorrosion inhibitor compound containing suspended particulates. Burnoutoccurring among these splices led to removal and replacement of all ofthe new connectors. In this study, the connectors removed from 102apartments were inspected for signs of overheating and for indicationsof abnormal conditions that might cause the failed connectors includedsamples that were applied to rated wire combinations and showed no signof abnormal installation or application conditions. Tests of thealuminum conductors from the apartments reveal no abnormalities thatcould account for the poor performance of the new connector. Theinhibitor compound inside the connector was determined to be of limitedeffectiveness in improving the wire-to-wire contact through the highresistance film on the aluminum wire surface. On the basis of the fieldfailures in combination with previously reported laboratory studies itis concluded that the connector is not suitable for permanent use withaluminum wire residential wiring systems
展开▼
