The FS-IR2003 is a single point liquid level switch that can operate in high pressure, high temperature, and aggressive
environments due to its stainless steel and glass construction. This level switch offers industrial supply voltages and outputs that can directly drive loads. This model has a wide operating voltage, which is from 5VDC to 24VDC. The output ways have two types, NPN and PNP. The sensor can detect the presence or absence of almost any liquid, and can be configured to output a high or low signal in either a wet or dry state.

The microcontroller based Stainless Glass Range liquid level switches are solid state, incorporating an infra-red LED and
phototransistor which are optically coupled by the tip when the sensor is in air. When the sensing tip is immersed in liquid, the infrared light escapes making the output change state. The sensor can detect the presence or absence of almost any liquid type; oil or water based. It is insensitive to ambient light and is not affected by foam when in air or by small bubbles when in liquid.