Explanation Of The Structure Of The Arc-starting Rod On The Insulator

In high-voltage transmission lines, a metal arc-starting rod is installed at the end of the polymer deadend insulator terminal to form a parallel gap device. The arc-starting rod is typically paired with a corresponding fitting, one connected to the high-voltage side and the other to the grounding side, forming a pair of electrodes.

The metal arc-starting rod is installed in conjunction with the porcelain dead end insulators. In the event of an overvoltage or lightning strike causing a flashover, the arc will preferentially break down between these two arc-starting rods. The resulting discharge path allows the arc to bypass the suspension insulator surface, protecting the suspension composite insulator from external discharge or damage.

The arc-starting rod can be structurally designed with a bent shape. Some models have an insulating sleeve covering the rod body and a spherical protrusion near the mounting base. This design facilitates fixing the arc to the rod end during arc ignition and guides the arc to a safe path.

For composite suspension insulator arc-starting lines made of materials such as ceramic or glass, the arc-starting rod is an important component of its lightning protection and breakage avoidance structure.