What is a surge arrester and what does it protect against?

Surge arrester limits overvoltage transients to safe levels. Protects equipment from lightning strikes, switching transients, and power line disturbances.

How does a surge arrester actually work?

Non-linear varistor changes resistance with voltage. At normal voltage, blocks current. Surge detected, resistance drops instantly, diverting transient to earth.

What are the different types of surge arresters and when to use each?

Type 1: direct lightning strikes (highest energy). Type 2: distribution level (standard switching). Type 3: sub-panels/sensitive loads. Use Type 1+2 combination for complete protection.

When should I install surge arresters in my electrical system?

Install if facility exposed to lightning risk, has sensitive equipment (IT/HVAC/controls), or experiences frequent power anomalies. Mandatory in high-risk zones.