What equipment helps mitigate excessive voltage surges on a distribution line?

The correct answer is the lightning or surge arrestor because its primary function is to protect electrical equipment from voltage surges, particularly those caused by lightning strikes or switching operations on the grid. These devices are designed to divert the excessive voltage away from sensitive components and direct it to the ground, thereby preventing damage to transformers, circuit breakers, and other equipment along the distribution line.

Surge arrestors are strategically installed on overhead lines and substations to ensure a rapid response to any surge event, clamping the voltage at a safe level. This protective mechanism is crucial in maintaining the integrity and longevity of the entire electrical system.

Other devices mentioned, like a recloser, help in automatic fault isolation and restoration but do not specifically mitigate voltage surges. Capacitors are used for power factor correction and voltage support but do not provide surge protection. Transformers manage voltage levels in the system but are not designed to absorb or divert surges. Hence, the functionality of a lightning or surge arrestor makes it the ideal choice for protecting against voltage surges on distribution lines.