What is a protective device that limits surge voltages by discharging or bypassing surge current?

A surge arrestor is designed specifically to protect electrical systems by diverting excessive voltage away from sensitive equipment. When a surge voltage occurs—often due to lightning strikes or power fluctuations—the surge arrestor engages and provides a path for the surge current to travel safely to ground. This limits the voltage that reaches the protected device, preventing damage from transient overvoltage conditions.

Surge arrestors are typically used in various applications, including residential and commercial electrical installations, to ensure that high voltage spikes do not affect electronic devices. They are fundamental components in protecting the integrity of electrical systems, allowing normal operation while safeguarding against unexpected voltage surges.

In contrast, other options, while closely related, do not capture the specific definition and function of a surge arrestor as effectively. The terms surge protector and surge suppressor can sometimes be used interchangeably in conversations, but they usually refer to devices that may not always fully mitigate the surge the way a surge arrestor does, particularly in high-energy situations. Surge limiters function to clamp down on surges but may not have the same protective capabilities in terms of discharging that a surge arrestor possesses.