Expulsion type lightning arrester is also known as a protector tube. It consists of – (i) a tube made of fibre which is very effective gas-evolving material (ii) an isolating spark gap (or external series gap) and (iii) an interrupting spark gap inside the fibre tube. During operation arc due to the impulse spark-over inside the fibrous tube causes some [...]
There are two main ways in which lightning affects a line: 1. Direct Lightning Strokes 2. Surge Due to Electrostatic Induction. Way # 1. Direct Lightning Strokes: A direct stroke can take place in several ways. In one way a cloud attains a large amount of charge, it induces an opposite charge on the tall objects, such as temples, churches [...]
All the electrical equipment must be protected from severe damage due to the lightning strokes. The problem of protection of power systems against lightning can be studied under the following heads:- 1. Protection of power stations and substations from direct lightning strokes 2. Protection of overhead transmission lines from direct lightning strokes 3. Protection of electrical equipment from travelling waves. [...]