A good Air Circuit Breaker (also generally known as an Air Blast Circuit Breaker or ACB) is
surely an automatically operated electrical button that uses air
to guard an electrical circuit from damage caused by excess current from a strong overload or short
routine. Its primary function could be to interrupt current flow following a fault
is discovered. When this happens, an arc
will appear between the contacts which may have broken the circuit.
Air circuit breakers use squeezed air to blow available the arc, or however, the contacts are rapidly swung right into
a small sealed chamber, the escaping from the displaced air, thus
forced out the arc.
Such a circuit breaker operates in air at atmospheric demand.

After the development on the oil circuit breaker, the medium voltage
air circuit breaker have been largely replaced by fat circuit breakers worldwide.

The working principle on this breaker is
rather more advanced than those in any others
of circuit breakers. The key aim of all types of circuit breaker is to
counteract the reestablishment of arcing after current zero by
setting up a situation where in this contact gap
will stand up to the system recovery voltage.

Mid-air circuit breaker does a similar but in different approach.
For interrupting arc the item creates an arc voltage more than the supply voltage.
Arc voltage is synonymous with the minimum voltage expected maintaining the arc.
This circuit breaker raises the arc voltage by mainly three different ways,

It may increase the arc voltage by customizable the arc plasma.
Because the temperature of arc plasma is actually decreased, the mobility
belonging to the particle in arc plasma is reduced; hence
more voltage gradient is required to maintain the arc.
This could increase the arc voltage simply by lengthening the
arc way. As the length with arc path is elevated, the resistance of the path is increased, and
hence to keep the same arc current more voltage is necessary to be
applied throughout the arc path. That implies arc voltage is increased.

Splitting up the arc into a number of series arcs also raises the arc voltage.