Insulator Types
Insulators are widely used in overhead transmission lines to provide mechanical support and electrical protection, as well as in distribution lines and substations. In transmission and distribution (T&D) systems, overhead conductors are usually supported by towers and poles, which are both grounded. Hence, an insulator must be deployed between the tower or pole body and current-carrying conductor to prevent the flow of current from the conductor to the earth via the grounded supporting towers or poles.
Depending on voltage considerations, different kinds of insulators are used in power systems. A look at some types of insulators and the conditions under which they are deployed.
There are 5 types of insulators used in transmission lines as overhead insulation:
1. Pin Insulator
2. Suspension Insulator
3. Strain Insulator
4. Stay Insulator
5. Shackle Insulator
Pin, Suspension, and Strain insulators are used in medium to high voltage systems. While Stay and Shackle Insulators are mainly used in low voltage applications.
