Adafruit
Optomax Digital Liquid Level Sensor
The Optomax is an optical liquid level sensor that detects the presence or absence of almost any liquid — oil or water based. Inside the polysulfone housing,...
The Optomax is an optical liquid level sensor that detects the presence or absence of almost any liquid — oil or water based. Inside the polysulfone housing, an infrared LED and matching phototransistor work together: when dry, the IR light reflects internally back to the sensor; when the tip is immersed in liquid, the light escapes and the output switches.
The sensor provides a push-pull digital output capable of sinking or sourcing up to 100 mA, allowing it to directly drive small loads like transistors or relays. It operates on 4.5–15.4 V DC and is insensitive to ambient light, foam (when in air), and small bubbles (when in liquid).
Key Features
- Optical Sensing – No moving parts for reliable, maintenance-free operation
- Push-Pull Output – Sinks or sources up to 100 mA for direct load driving
- Wide Supply Range – 4.5–15.4 V DC with reverse polarity, ESD, and transient protection
- Chemical Resistant Housing – Polysulfone construction for use with a wide range of fluids
- Compact Form Factor – Suitable for space-constrained installations
- Leak Detection Capable – Sensitive enough to detect small amounts of liquid when positioned correctly
- Fast Response – Repeatable switching point with optional output delays for sloshing applications
Wiring
- Blue/Black Wire – Ground
- Red Wire – Supply voltage (4.5–15.4 V DC)
- Output – Supply voltage when dry, 0 V when wet
Specifications
- Output Type – Push-pull, up to 100 mA sink/source
- Supply Voltage – 4.5–15.4 V DC
- Housing Material – Polysulfone (chemically resistant)
- Operating Temperature – −25 °C to 80 °C
- Detection – Oil and water-based liquids
Package Contents
- 1× Optomax digital liquid level sensor
Jargon buster
Plain-language definitions for the technical terms used above.
- LED
- A light-emitting diode is a small electronic component that lights up when current flows through it in the correct direction. In this kit, LEDs create the flashing effect, so polarity and correct soldering matter for the project to work.
- phototransistor
- A light-sensitive transistor that changes its electrical output when light hits it. Compared with a modulated IR receiver, a simple phototransistor can be more affected by ambient light, so it may need extra filtering or careful setup.
Find this product in
Brands
Sensors & Input
Related Tutorials
Free guides on learn.littlebird.com.au