Electrical performance of 115 kV transmission lines fiberglass crossarms aged in field

This paper presents the results of an investigation on the ac voltage and lightning impulse performance of 115 kV transmission lines fiberglass crossarms aged in the field. The crossarms removed after 10-20 years from service, crossarms stored outdoors but not in service and new crossarms were examined. The evaluation of electrical performance was based on flashover voltage value at standard lightning impulse voltage and the ac flashover voltage. The CFO voltages for lightning impulses were measured under dry and wet conditions, and the tests were conducted with positive and negative polarity. The obtained flashover voltages show some differences in electrical strength of fiberglass crossarms removed from service