Liquid Level Switch
Model WB

The Model WB is a special purpose level switch designed for use with sewer diversion and automated irrigation systems. The WB gives an electrical signal after a given amount of rain has fallen. This signal is used to divert storm water away from the normal water treatment facilities and into the storm sewer system, or to activate a sump pump. The signal can also be used to omit an irrigation cycle for country clubs, agriculture firms, or others that are affected by rain. Particularly valuable for large expanses of land where localized storms might cover one area, but not another. By use of rain switches in different areas, the irrigation system will operate only in those areas where rainfall did not occur.

Unless otherwise specified, the electrical signal will be given after 1/4" of rain falls. This can be adjusted in the field up to 3/10" of an inch of rainfall. If the solenoid valve option is selected, this point is not field adjustable.


Body: The body or collecting chamber is an all welded assembly of 300 series stainless steel.
Collector: The collecting part or funnel is made of 300 series stainless steel with a screen to prevent debris from entering the body.
Specific Gravity: The minimum standard specific gravity is 1.0.
Float: One 3-1/2" round in 300 series stainless steel is standard.
Trim: The float rod and trim is made of 300 series stainless steel.
Switches: One switch per unit.
Conduit Connection: A weather proof conduit box is supplied and attached to the switch assembly. The box has 1/2" NPS connections.

Optional Features:

Base: The unit can equipped with a mounting stand and four 3/8 bolt holes. This stand can be removed for other installations.
Indicator Lights: Red and green LED's will be installed on the conduit box as well as two 3 din terminal blocks.
Solenoid Valve: A 120 VAC is installed on the drain port.
Manual Ball Valve: A 316 stainless steel ball valve is added to the drain port.


Starting in the unactuated position, a rising liquid level will lift the float and rod, raising the actuating piston towards the magnetic operating zone of the switch assembly. A permanent magnet, located within the switch assembly, snaps forward from the magnetic attraction. In doing so, a plunger is depressed, actuating a micro switch. When the level decreases, the float falls away, pulling the actuating piston to its original position, releasing the permanent magnet, re-setting the switch assembly to its unactuated position.