Design Function of Insulator Fins or Ridges
On high-voltage poles or towers, you may notice insulators with multiple ridges. These fins or ridges along the sides of insulators increase the creepage path the distance electricity must travel across the surface thus reducing the chance of flashover, especially when wet or contaminated. They improve performance without making the insulator longer. Additionally, the shape helps rainwater drip rather than form a continuous conductor, enhancing insulation even in adverse weather.
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