The Vacuum Circuit Breaker VCB commonly applies on 10 to 35kv medium voltage power line. It has indoor type, of which the circuit breaker is installed in the HXGN or KYN28 type switchgear, combined with isolation switch and earthing switch. The outdoor type Vacuum Circuit breaker is pole mounted, of which the isolation switch is integrated with the switchgear.
On visual, the Vacuum Circuit Breaker VCB has the insulating cylinder or cast pole as insulation and encapsulation materials of vacuum interrupters, where is on the back of the Vacuum Circuit Breaker VCB. However, the Air Circuit Breaker ACB use ambient air to extinguish the arc through splitters. Ever more, the Air Circuit Breaker ACB is applied on the low voltage distribution circuits. It has input and output busbar on the back.
On functional, the Vacuum Circuit Breaker VCB is applied on the medium voltage distribution line which design to protect distribution transformers and power distribution line. Meanwhile, it need to combine with the independent relay to fulfil the protection function, such as differential protection, earthing protection etc. However, the Air Circuit Breaker ACB is applied on the low voltage electrical circuit which design to protect the circuit and electrical appliances. It has built in trip unit to fulfil the protection function, such as long time protection and earthing protection.
