Soil Moisture Sensor Module — Analog/Digital Output, Adjustable Threshold
Soil Moisture Sensor Module — Analog/Digital Output with Adjustable Threshold
The Soil Moisture Sensor Module detects water content in soil by measuring resistance between two probes. It provides both analog and digital outputs, making it suitable for simple threshold-based alerts or precise moisture monitoring in automated irrigation systems. The onboard LM393 comparator and potentiometer let you set a trigger level for the digital output, while the analog output connects directly to a microcontroller ADC pin for real-time readings.
Key Specifications
| Specification | Value |
|---|---|
| Operating Voltage | 3.3V – 5V DC |
| Output Type | Analog (0 – VCC) and Digital (0 / VCC) |
| Comparator | LM393 with threshold adjustment |
| Probe Material | Nickel-plated copper with protective coating |
| PCB Dimensions | 36 mm x 15 mm x 7 mm |
| Probe Length | 65 mm |
What You Can Build With This
- Automatic garden watering system that activates a pump when soil is dry
- Indoor plant monitor with LED or alert when moisture drops below a set point
- IoT soil tracker that logs moisture data to the cloud using an ESP8266
- Agriculture automation prototype for greenhouse irrigation management
Compatibility
This module works with any microcontroller that has an analog input, such as Arduino Uno, Nano, ESP32, ESP8266, and Raspberry Pi Pico. For Raspberry Pi boards without analog pins, use an external ADC like the MCP3008. It runs on 3.3V or 5V logic, and the analog output scales with the supply voltage—calibrate accordingly in your code.
Wiring Notes
Connect VCC to 3.3V or 5V, GND to ground. For analog monitoring, wire AOUT to an analog pin. For digital threshold, use DOUT and adjust the on‑board potentiometer until the indicator LED switches at your desired moisture level. Keep the electronics away from direct water contact; use the included jumper wires to mount the sensor remotely.
Why Buy from Compoden
Every component is sourced from verified suppliers and tested for compatibility before listing. We've spent 10 years building projects for makers, schools, and institutions across India. Ships from Bengaluru in 3-5 days. If defective on arrival, replace within 7 days.
Is this compatible with Arduino Uno?
Yes, connect VCC to 5V, GND to GND, and AOUT to A0 for analog readings. The digital output can go to any digital pin.
How do I calibrate the digital threshold?
Turn the potentiometer while the probes are in dry soil until the DOUT LED just lights up; insert into wet soil and adjust so the LED turns off. Repeat for precision.
Will the probes corrode over time?
Nickel-plated probes resist corrosion, but constant wet soil can eventually degrade them. For long-term use, consider capacitive sensors or intermittent power to reduce electrolysis.
📦 Free Setup Handoff Document Included
Every Compoden order includes a free setup handoff document — step-by-step instructions to get your component working within minutes. Download it via QR code on your package. The handoff document is also trained to help you troubleshoot the majority of problems.
Ask Soldr above what you can build with this — it knows every Compoden kit this part appears in.
Shipping Information
- Prepaid Orders: ₹75 for orders up to ₹999, FREE shipping above ₹999
- COD Orders: ₹125 shipping + ₹50 COD fee = ₹175 total
- Delivery Timeline: Dispatch in 1-2 days, delivery in 2-7 days depending on location
Returns & Warranty
- 7-Day Return: Manufacturing defects only (approval required)
- Warranty: 7 days from delivery
- Non-Returnable: Batteries, consumables, cut wires, clearance items