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Vacuum contactors extinguished solitary ability, good pressure resistance, high operating frequency, long life, no outside arc spray, small size, light weight, long maintenance cycle.

Vacuum interrupter vacuum contactor demanding manufacturing process, if poor processes, vacuum interrupter easily fall. Contact material material is bad, when breaking current will be "over-voltage shutoff" phenomenon, that is, when breaking current, due to the extinction of the vacuum interrupter ability is very strong, is not a natural arc current zero crossing cut off, but from a value of the current abruptly falls to zero, whereby the emergence of a high overvoltage. Closure voltage would endanger the safe operation of electrical equipment.