Table of Contents
Interfacing Raindrop Sensor with Arduino: Today’s tutorial is about the interfacing of Raindrop sensor with Arduino. The rain sensor module is an easy tool for rain detection. It can be used as a switch when raindrop falls through the raining board and also for measuring rainfall intensity. The module features, a rain board and the control board that is separate for more convenience, power indicator LED and an adjustable sensitivity though a potentiometer. We will divide this tutorial in following sections:
- Working Principle of Raindrop Sensor
- Pin Configuration
- Specifications
- Circuit Diagram
- Testing the Circuit
- Applications
Working Principle of Raindrop Sensor
Raindrop sensor is basically a board on which nickel is coated in the form of lines. It works on the principal of resistance. When there is no rain drop on board. Resistance is high so we gets high voltage according to V=IR. When rain drop present it reduces the resistance because water is conductor of electricity and presence of water connects nickel lines in parallel so reduced resistance and reduced voltage drop across it.
Pin Configuration Raindrop Sensor
It consists of two parts one is a black board with nickel layers on it and other is an intergrated chip provided with some output pins.Board has 2 output pin and chip has 6 pin
Chip pins are
- +
- –
- Vcc
- GND
- A0
- D0
Board Pins are
- +
- –
Pin configuration is as given in picture
Specifications of Raindrop Sensor
- Adopts high quality of RF-04 double sided material.
- Area: 5cm x 4cm nickel plate on side.
- Anti oxidation, anti-conductivity, with long use time.
- Comparator output signal clean waveform is good, driving ability, over 15mA.
- Potentiometer adjusts the sensitivity.
- Working voltage 5V.
- Output format: Digital switching output (0 and 1) and analog voltage output AO.
- With bolt holes for easy installation.
- Small board PCB size: 3.2cm x 1.4cm.
- Uses a wide voltage LM393 comparator.
Circuit Diagram of raindrop sensor interfacing with arduino
Connect as follows
Rain Drop Black Board +ve with Integrated Chip +ve
Rain Drop Black Board –ve with Integrated Chip –ve
Integrated Chip Vcc with Arduino Board +5V
Integrated Chip GND with Arduino Board GND
Integrated Chip D0 with Arduino Board Digital pin 2
Integrated Chip A0 with Arduino Board Analog pin A1
The analog output is used in detection of drops in the amount of rainfall. Connected to 5Vpower supply, the LED will turn on when induction board has no rain drop, and DO output is high. When dropping a little amount water, DO output is low, the switch indicator will turn on. Brush off the water droplets, and when restored to the initial state, outputs high level.When no rain digital output is 1 and analog output gives 1023 max value. When rain is present digital output is 0 and analogue output is much less than 1023. Using potentiometer on chip we can control the turning OFF point of digital pin at some value of analog pin.
Video lecture on raindrop detector project
Testing the Raindrop Sensor
Following components will be used
- Arduino Board
- Rain sensor module
- Pin connectors
- USB cable
Follow the steps to run program
- Connect the components based on the figure shown in the wiring diagram using pin connectors. VCC pin is connected to the 5V power supply, GND pin is connected to the GND, DO pin is connected to a digital I/O pin and the AO pin is connected to the analog output pin. Pin number will be based on the actual program code.
- After hardware connection, insert the sample sketch into the Arduino IDE.
- Using a USB cable, connect the ports from the Arduino to the computer.
- Upload the program.
- See the results in the serial monitor
Code for rain drop sensor interfacing with arduino
void setup() { // put your setup code here, to run once: Serial.begin (9600); pinMode (2 , INPUT); } void loop() { // put your main code here, to run repeatedly: int value = analogRead(A1); int digital = digitalRead(2); Serial.println (value); Serial.println (digital); delay(2000); }
Applications:
- On windscreen of car to automatically start the wipers
- On roof of houses and offices to take necessary action against rain
- In Weather Station
what will be the threshold value of the rain drop sensor?
pls send answers fast
Sketch uses 2262 bytes (7%) of program storage space. Maximum is 32256 bytes.
Global variables use 188 bytes (9%) of dynamic memory, leaving 1860 bytes for local variables. Maximum is 2048 bytes.
How can I get sensor to not be so sensitive? Approximately 1 droplet of water will equal a flood and a few sprinkles equal a rain warning.