Jabsco part # 4732-0000

The Jabsco 4732-0000 is a vacuum switch used for automatically turning off a pump if it runs dry. The 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 shutoff 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 attended at all times. 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 switch contains a spring loaded diaphragm sensitive to a vacuum of not less than 2-1/2 Inch Hg (mercury). If a vacuum switch is used with a pump handling corrosive fluids, 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.

Switch is not ignition protected. Do not use in bilge area of vessels with gasoline engines or equipment.