
Low-voltage residential, industrial, and commercial applications utilize air or vacuum as the
arc-interrupter mechanisms in circuit breakers. Commercial, industrial, and utility
applications, operating at voltages above 1000 V typically may use any of the mediums
depending upon the application.
Several methods are commonly used to extinguish an arc developed when a circuit breaker
opens under fault or load conditions. They include:
Lengthening the arc path
Deflection of the arc with a differential pressure
Diversion of the arc to secondary contacts
Zero point quenching
Diversion of the arc with a magnetic field (blowout coils)
Intensive cooling of the