Electrical performance of fiberglass crossarms aged in transmission line

The authors present the results of an investigation of the electrical performance of a 115-kV transmission line fiberglass crossarm. Crossarms removed from service and companion crossarms stored outdoors but not in service were examined. The evaluation of electrical performance was based on flashover voltage value at AC voltages and at standard lightning impulse voltages, measured under dry and wet conditions. The impulse voltage waveshape used in all the laboratory investigations was a standard 1.2/50- mu s wave as described in IEEE Standard 4 and had positive polarity. The flashover voltages obtained showed no large difference in electrical strength between fiberglass crossarms removed from service and those stored outdoors.<
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