The Optomax Digital series of liquid level switches have the capacity to detect almost any liquid type whether it is oil or water based. Each unit incorporates an infra-red (IR) LED emitter, a phototransistor and a microcontroller within a housing which can be as small as 22.7 mm in length and 12 mm in diameter.

Being basically solid-state electronics devices rather than conventional mechanical float switches, the new switches from SST Sensing Ltd. are not prone to jamming or wear and tear and feature long, maintenance-free operational lifespans. The performance of the liquid level switches is not affected by ambient light thanks to the advanced optical design employed, as well as propriety signal conditioning algorithms. Foam layers on top of the liquid do not affect the devices.

Driven by a 4.5 V to 15.4 V DC supply, these low power devices draw a maximum current of 2.5 mA. The sensors are available with high or low in air outputs as well as a PWM option for maximum reliability and fail-safe operation. They are capable of supporting pressures of up to 20 bar and offer an operational temperature range of -25°C to +80°C (with extended range versions covering -40°C to +125°C).