The role of lightning arrester is used to protect various electrical equipment in the power system from lightning overvoltage, operating overvoltage, power frequency transient overvoltage shock and damage of an electrical appliance. 

The main types of lightning arrester are protection clearance, valve type lightning arrester and zinc oxide lightning arrester. The protection clearance is mainly used to limit atmospheric overvoltage and is generally used to protect the incoming line segments of distribution systems, lines and substations. Valve type arrester and zinc oxide arrester are used in substation and power plant protection, under 500KV system is mainly used to limit the atmospheric overvoltage, in the ultra high voltage system will also be used to limit the internal overvoltage or as the backup protection of the internal overvoltage.

Lightning arrester can protect communication equipment effectively. Once abnormal voltage occurs, lightning arrester will act and play a protective role.