Arc Interruption in circuit breakers
Electric arc is a highly
ionized gas at very high temperature. Current passes through the arc by means
of moving ions under the effect of electric field. To interrupt the arc, the
rate of deionization must be greater than the rate of ionization. This can be
achieved by one or more of the following.
1- Cooling the arc.
2- Increasing the voltage
drop across the arc by increasing its length.
3- Splitting the arc into
several arcs.
The above three methods of
arc interruption are used in air C.B. (Low voltage) and all d.c breakers.
