DDC-JQ-B series electro-magnetic vacuum gas valve is a special valve installed in rotary vane vacuum pump. The valve and pump should be connected in the same power. The pump start / stop directly controls the valve open / close. When the pump stops working or there is a sudden interruption of the power supply, the valve will automatically close the vacuum system and fills gas into pump through the pump gas inlet. In this way, it prevents the pump oil return to the vacuum system.

The applicable active medium of this valve are air, non-corrosive gas.