Basic Principle
The Scanjet Macron displacement type float level switch consists of a compression spring, displacer and switch unit in which a micro switch and magnet.

The operation is based on simple buoyancy whereby a spring is loaded with weighted displacers which are heavier than the liquid.

Immersion of the displacers in the liquid results in buoyancy force change, which moves the spring upward, Simultaneously the spring is retracted of the extended and the attraction sleeve moves upward into the field of external magnet in the switch unit.

The contact of micro switch is changed by magnetic force as the attraction sleeve is in the field of magnetic point force.

This principle allows adjustment of the switching point by moving the displacer along the guide pipe.

Application
Displacement type float level switches are widely used for HFO storage and settling tanks, MDO, sludge tanks, fresh water tanks, lube oil tanks and others for high level overfill alarms.