Abstract: A three-position vacuum switch for realizing external grounding of a load side by using a connected busbar overcomes the problems in the prior art that load side grounding is realized depending on the opening and closing of a vacuum arc extinguishing chamber, a misoperation easily occurs because an operator cannot see the grounding situation intuitively, and when an operating mechanism machine has a problem, it needs to have a grounding line plugged in externally, which cause inconvenient operations and huge safety risks, characterized in that a connected busbar is hinged on front and back sides of a load socket, the vacuum arc extinguishing chamber is connected to the connected busbar by using a pin, the connected busbar is electrically connected to a grounding socket to realize primary grounding, and the vacuum arc extinguishing chamber is electrically connected to the grounding socket to realize auxiliary grounding.

Abstract: A three-position vacuum switch for realizing external grounding of a load side by using a bridge switch overcomes the problems in the prior art that load side grounding is realized depending on the opening and closing of a vacuum arc extinguishing chamber, a misoperation easily occurs because an operator cannot see the grounding situation intuitively, and when an operating mechanism machine has a problem, it needs to have a grounding line plugged in externally, which cause inconvenient operations with huge safety risks, a complicated structure and relatively high cost, characterized in that a bridge grounding switch is provided on the other side of the three-position vacuum switch to realize external grounding of the load side via the bridge grounding switch.