Description

MH Sensor Series

A hygrometer for soil. This is an easy to use sensor module you can use to sense moisture content in soil, suitable for agricultural projects. It comes with a fork type electrode you can use to measure the electrical resistance of soil. The moisture content in soil affects its electrical conductivity, changing the resistance and therefore this can be sensed using the electrode and the sensor circuit.

Note : this sensor can works with both analog and digital mode. You can connect the analog output (AO) pin to Arduino to read the level of moisture in soil, or digital output (DO) to sense the threshold of soil moisture level. Adjust the potentiometer (a.k.a. trimmer) to set the digital output (DO) sensitivity.

Specific Features

• Comes with fork type electrode for measuring the moisture level
• The moisture content in soil affect the electrical resistance of soil
• The higher the moisture level, the lower the analog reading. You’ll need to calibrate the value by yourself following your case study.

 

Common Features

• Logical IC : LM393
• Operating voltage : 3.3 – 5V
• Output current : ?15 mA
• Adjustable sensitivity via potentiometer
• Comes with LED indicators for POWER and OUTPUT
• Fixed bolt holes for easy installation

 

Wiring

Label	Meaning	Connection
VCC	Power source	Connect to 3.3V or 5V of system
GND	Ground	Connect to GND of system
DO	Digital Output	Connect to any digital IO pin
AO	Analog Output	Connect to analog input pin

 

Files & Documentation

• Tutorial : Arduino Soil Moisture Sensor – Instructables
• Tutorial with code : How to Test Soil With Arduino and an FC-28 Moisture Sensor – MakerPro
• Tutorial with code : How Soil Moisture Sensor Works and Interface it with Arduino – LastMinuteEngineers