In this tutorial, we are making a circuit of a Rain detector switch using a relay. It prevents your electronic appliances outside your house from short-circuiting and damaging by automatically switching them off when rainfall starts. This circuit is easy, useful, and inexpensive as it is using only a few components. It doesn’t need much power it can be operated easily on 6 volts DC.
Even if you are someone who isn’t familiar with electronics or Veroboard you can still make this circuit. The sensor can be made by simply attaching thin metal strips to a piece of wood, plastic, etc. but make sure to give no more than a 1mm gap between the strips. Or if you want you can make it by using Vero.
Hardware Components
The following components are required to make Rain Detector Switch Circuit
| S.no | Component | Value | Quantity |
|---|---|---|---|
| 1. | Battery | 6V | 1 |
| 2. | Sensor | – | 1 |
| 3. | Variable Resistor | 300K | 1 |
| 4. | Diode | 1N4001 | 1 |
| 5. | Relay | 6V | 1 |
| 6. | Transistor | BC547B | 1 |
BC547 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of BC547
Rain Detector Switch Circuit
Working Explanation
The working of this circuit is quite simple. This circuit is operating on 6 volts DC. A sensor is used to detect the presence of water droplets, this is really sensitive to moisture so it will always give accurate results. To adjust the sensitivity of this circuit we have used a 300K ohms variable resistor. When the sensor senses the raindrop it passes the voltage to the circuit as water is a great conductor of electricity. We are using a BC547B NPN transistor in this circuit that is acting as a switch for the 6V Relat connected with it.
On receiving the required 6V voltage the transistor will switch on and activate the Relay as well. In this way whenever it starts to rain the relay will turn off the electronic appliances and save them from short circuits or damage.
Applications and Uses
This circuit can be used not only outside your home but also where there are chances of your appliances getting damaged due to waterfalls.
