Multi-break arc extinguishing is a bridge-type contact device with a dual-breakpoint structure [1-2], which is applied in relays, contactors, load switches, medium and low-voltage circuit breakers and other switchgear [2]. When the contacts are separated, two breakouts generate mutually connected arcs. Under the action of electric force, they move towards both sides, causing the arcs to elongate and cool down and extinguish [4].
This type of contact has two effective arc-extinguishing areas. For small-capacity AC contactors with a rated voltage of 380V or less and a current of 20A or less, arc extinguishing can be achieved using the near-cathode effect when the current naturally crosses zero. When the current is 20-80A, an arc starter plate or the use of circuit electric force blowing arc in combination with the dual-breakpoint arc extinguishing is required. The gap of the dual-breakpoint contact is small and the structure is compact, but it needs to be made of silver or silver-based alloy materials, which is costly [3], and the contact pressure and higher closing force need to be increased [5].