Horn Gap Lightning Arrestor
A H orn gap arrester is a protective device used in electrical power systems to safeguard transformers, insulators, and transmission lines from high-voltage surges caused by lightning . It uses an air gap that arcs over during a surge, diverting the excess voltage safely to the ground. Construction and Parts Horn-Shaped Electrodes: Two metal rods shaped like horns, separated by a small distance. The gap gradually widens as it moves upward. Series Resistance: Connected to one side to limit the flow of follow-through current after the surge has discharged. Choke Coil: Connected to the line side; it offers low reactance to normal frequencies but high reactance to high-frequency transients, preventing surges from entering the protected equipment. Porcelain Insulators: Used to mount the horns safely on the poles. [ 1 , 2 , 3 ] Working Principle Under normal operating voltages, the air gap acts as an insulator, preventing current from jumping between the horns. When a...