Power Supply Basics: What Is a Surge and Surge Protection?

A surge, also known as a transient voltage spike, literally means an instantaneous overvoltage exceeding the normal operating voltage. Essentially, a surge is an intense electrical pulse that lasts only a few millionths of a second. Surges can be triggered by heavy-duty equipment, short circuits, power switching operations or large engines. Products equipped with surge suppression components can effectively absorb sudden massive energy and protect connected devices from damage.

A Surge Protective Device (SPD), also referred to as a signal lightning protector, is an electronic apparatus that provides safety shielding for all types of electronic equipment, instruments and communication lines. When external interference generates sudden peak currents or voltages in electrical circuits or communication lines, the SPD will conduct and divert current within an extremely short time, thus preventing surges from damaging other equipment in the circuit.