Vacuum Switch

Xylem’s Jabsco Vacuum Switch is an electrical device wired into the power circuit to an electric motor or electric clutch. When the switch is connected to the suction side of a pump, it senses the break in vacuum if the pump runs out of liquid. The break in vacuum causes the switch to open the circuit and shut off the motor or deactivate the clutch.

The Vacuum Switch is generally installed in a pumping system when transferring or pumping a limited amount of liquid when the pump cannot be always attended. The switch provides automatic shutoff when the pump runs dry, helping to prevent damage to the pump. Normally, the switch is manually restarted, although it is possible with electric motor and clutch installations to wire a momentary switch, float, or liquid level device across the terminals of the Vacuum Switch to reactivate the system remotely or automatically.

The switch case and diaphragm enclosure are cad-plated or enamel-coated steel and could be subject to corrosive attack from chemicals or chemical fumes. The diaphragm is neoprene.

The switch is normally mounted on the inlet side of the pump, between the pump and liquid source. The Vacuum Switch contains a spring-loaded diaphragm sensitive to a vacuum of not less than 2-1/2″ Hg (mercury).

If the Vacuum Switch is used with a pump handling corrosive fluid, the switch life may be extended by mounting the switch remotely and connecting the switch to the pump with stainless steel tubing or hard plastic tubing. All connections must be AIRTIGHT and non-collapsible.

The Jabsco Vacuum Switch is ideal for various applications, including:

• Emptying or transferring non-flammable liquids from drums and carboys
• Remote bilge pumping
• Dewatering

Note: The diaphragm is neoprene and, therefore, not suitable for prolonged contact with petrochemicals.