Like string insulators, suspension insulators are flexible insulator strings that are made up of some porcelain or glass disk insulators connected to each other by metal connectors. Widely used in medium and high voltage transmission lines.

There are two types of suspension insulators: cap-pin insulators and interconnect insulators (also known as Hewlett-type insulators), which are two designs that are connected using different metal connections.

For polar wires where the conductor hangs from the bottom of the insulator, use a cross arm to hold the insulator in place. Cross arms ensure that the insulator remains stable when attached to a pole or tower.

The voltage capacity of the insulator is determined by the platter. The more boards, the higher the voltage capacity

Various types of end fittings can be attached to suspension insulators such as Y-clamps, tongues, clevises, sockets, balls and eyes.

There are some differences between suspension insulators and string insulators. Suspended insulators are used in a vertical position and bear their own gravity, while string insulators are installed horizontally and bear a certain conductor tension.

What is a suspension insulator?

Definition: Suspended insulators protect overhead transmission lines like conductors. Usually, it is made of ceramic material and consists of a single or a string of insulating discs suspended from the tower. It works above 33KV and overcomes the limitation of pin insulators as follows.

Its size and weight increase above 33KV

Difficult to handle and replace unit insulators

Replacing damaged insulators is expensive.

Properties of Insulator Materials