Optomax Digital Liquid Level Sensor

Optical point-level switch that outputs a digital signal when submerged; no moving parts or oxidizing contacts. Suitable for water detection, tank fill/empty sensing, and damp-environment monitoring.

Logical pinout · physical placement not verified

BlueBlack wire
Ground lead. Adafruit product page says to connect the Blue/Black wire to ground.
Type · GroundVoltage · 0V / ground
Red wire
Supply lead. Adafruit product page says to connect the Red wire to 4.5-15.4VDC.
Type · PowerVoltage · 4.5-15.4VDC
Output wire
Push-pull logic-level liquid-detect output. Adafruit states dry output is the same as the red wire and wet output is 0V; output can sink/source up to 100mA.
Type · SignalVoltage · 0V when wet; same as red supply when dry; supply range 4.5-15.4VDC

Pin	Type	Function	Voltage
BlueBlack wire	Ground	Ground lead. Adafruit product page says to connect the Blue/Black wire to ground.	0V / ground
Red wire	Power	Supply lead. Adafruit product page says to connect the Red wire to 4.5-15.4VDC.	4.5-15.4VDC
Output wire	Signal	Push-pull logic-level liquid-detect output. Adafruit states dry output is the same as the red wire and wet output is 0V; output can sink/source up to 100mA.	0V when wet; same as red supply when dry; supply range 4.5-15.4VDC

Logical pinout · physical placement not verified

Pin details

3 connections

BlueBlack wire
Ground lead. Adafruit product page says to connect the Blue/Black wire to ground.
GroundVoltage · 0V / ground
Red wire
Supply lead. Adafruit product page says to connect the Red wire to 4.5-15.4VDC.
PowerVoltage · 4.5-15.4VDC
Output wire
Push-pull logic-level liquid-detect output. Adafruit states dry output is the same as the red wire and wet output is 0V; output can sink/source up to 100mA.
SignalVoltage · 0V when wet; same as red supply when dry; supply range 4.5-15.4VDC

Start wiring

Analog · UART · 3.3 – 5 V · Gravity

Verify supply voltage and logic levels before powering up.

Module pins: Red wire, Blue/Black wire, Output wire. Schematik maps them to your board in the app.

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