1.Water Level sensor specification: - Working voltage: DC 3~5V. - Working current: <20mA. - Sensor type: simulation. - Test range: 40mm x 16mm. - Workmanship: FR4 double side SMOBC&HAL. - Working temperature: 10~30'C. - Working humidity: 10%~90% no condensation. - Voltage: 5V. - With power supply indicator signal output LED indicator. - TTL level output TTL effective signal output is low level; Drive ability is about 100mA can directly drive relay buzzer mini fan etc. - Sensitivity can be adjusted by the potentiometer. - Control board dimension: 3 x 1.6mm. - Large scale raindrops sensor board: 5.4 x 4.0mm. 2.Application method: - Connect with 5V power supply when no water drop DO output is high level indicator light off; when has water drop DO output is low level indicator light on. - AO analog output can test the rainfall by connecting with the SCM AD port. - Comparator USES the LM393 chips stable work ability. - Working voltage: 3.3~5V. - With fixing bolt holes convenient to install. - PCB dimension: 3.2cm x 1.4cm. 3.Wiring instructions(3-line type): - VCC external connecting 3.3~5V. - GND external connecting. - DO digital output interface(0 and 1).