The Rain Drop Sensor Module is an essential environmental sensing tool designed to detect water droplets and moisture levels. At Electrapac, we recommend this sensor for hobbyists and engineers building smart home systems, automated weather stations, or rain-sensing wiper prototypes.

Product Overview

This module consists of two distinct parts: a large, high-quality sensing pad and a separate control board. The sensing pad features a nickel-plated surface to resist oxidation and improve conductivity. When a raindrop falls on the pad, it creates a conductive path, decreasing the resistance. The control board processes this change and provides both a precise analog voltage and a simple digital switching signal.

Key Features for Electrapac Customers

• Dual Signal Output: * Analog Output (AO): Provides a continuous voltage (0V–5V) proportional to the amount of water on the pad—ideal for measuring rainfall intensity.

  • Digital Output (DO): Allows you to set a moisture threshold using the onboard potentiometer to trigger an action (like closing a window).

• Anti-Oxidation Surface: The sensing pad is nickel-plated to prevent rust and corrosion, ensuring a much longer lifespan compared to cheaper copper-only versions.

• Adjustable Sensitivity: Features an onboard multi-turn potentiometer. You can fine-tune the sensor to trigger only for heavy rain or to react to a single drop of mist.

• Integrated LM393: The control module uses a high-precision voltage comparator for clean digital signals, making it compatible with all 3.3V and 5V microcontrollers.

• Easy Installation: Includes pre-drilled holes on both the pad and the control board for secure mounting to your project chassis or outdoor enclosure.

Wiring & Calibration Guide

Connecting the Electrapac Rain Sensor to your Arduino is straightforward. The control board has 4 pins for the microcontroller and 2 pins for the sensing pad:

1. VCC: Connect to 3.3V or 5V.

2. GND: Connect to common ground.

3. DO: Digital Output—goes LOW when rain is detected.

4. AO: Analog Output—voltage decreases as the pad becomes wetter.

Pro-Tip: For the most accurate readings, mount the sensing pad at a slight angle (around 15° to 30°). This allows water to run off the surface once the rain stops, preventing the sensor from staying "active" due to standing water after the weather has cleared.

Primary Applications

• Smart Home Automation: Automatically closing motorized windows or retracting awnings when it starts to rain.

• Weather Stations: Monitoring and logging rainfall patterns over time using an SD card or Wi-Fi.

• Automated Agriculture: Disabling irrigation systems during rain to conserve water and prevent over-watering.

• Auto-Wiper Systems: Creating a prototype for rain-sensing windshield wipers for RC cars or robotics.

• Basement Flood Alarms: Placing the pad on the floor to detect leaks or rising water levels.

Why Shop at Electrapac?

We supply the Premium Rain Drop Sensor Kit which includes the sensing pad, the LM393 control board, and the necessary jumper wires to get you started immediately. Visit us at www.electrapac.com for the environmental sensors that help you stay one step ahead of the weather.