What is the purpose of a lightning arrester?

The purpose of a lightning arrester is to protect against voltage surges, particularly those caused by lightning strikes or other transient voltage spikes. When a surge occurs, a lightning arrester diverts the excess voltage away from sensitive equipment and infrastructure, effectively shunting the harmful energy to the ground. This helps prevent damage to electrical systems and improves overall safety.

In the context of this question, while other functions such as disconnecting faulty circuits or regulating voltage are important in electrical systems, they do not specifically pertain to the primary function of a lightning arrester, which is focused on surge protection. Additionally, increasing current flow is not related to the role of a lightning arrester, as its main function is to safeguard against overwhelming voltage, not to alter the current state of the system.