Learn in the textbookFacility Management: Power Supply Measures and Energy Saving
DefinitionSurge protection (サージ防護) diverts the abnormally large voltage or current that rushes in for an instant, for example from lightning (a surge, サージ), so that equipment does not break down.
ExplanationA surge can reach equipment not only through power lines but also through communication lines. Countermeasures include power strips with built-in surge protection and surge protective devices (SPDs) fitted to distribution boards or lines.
AnalogyIt works like a river's flood channel. It turns sudden high water away from the main stream so the town does not flood.
Memory hookThe English word surge means a sudden rise or an onrushing wave. Picture the incoming wave of electricity being steered aside just before it reaches the equipment.