In this tutorial, we are making a project of an Automatic plant irrigator with a 555 timer IC. The purpose of this circuit is to water the plants automatically if you forget to water them or you are away from home.
We all know that plants need some extra attention and care, they get spoiled or die if they don’t get water frequently. Everyone gets busy with their life and they sometimes forget to water them so this circuit comes in handy in these situations. You can connect a water pump with the relay switch connected to the output of the circuit.
Hardware Components
The following components are required to make an Automatic Plant Irrigator Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | Input Supply DC | 9-12V | 1 |
| 2. | Probes | – | 2 |
| 3. | Transistor | 2N3904 | 2 |
| 4. | IC | NE555 Timer | 1 |
| 5. | Relay | 9-12V | 1 |
| 6. | Diode | 1N4007 | 1 |
| 7. | Resistor | 1K, 10K | 1, 1 |
| 8. | Variable resistor | 1M, 50K | 1, 1 |
| 9. | Electrolytic Capacitor | 100µF | 1 |
| 10. | Ceramic Capacitor | 0.1µF | 1 |
NE555 IC Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 555 Timer
2N3904 Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 2N3904
Automatic Plant Irrigator Circuit
Working Explanation
The operating voltage of this circuit is 9 to 12 V DC. The circuit is divided into two sections, the first section has a moisture circuit built in it and the other section has a timer circuit built around a 555 timer IC. For the detection of the moisture, we have used two probes, these can be inserted into the soil of your plants.
The probes will detect the water contents in the soil of the plants, if enough water is present in the soil then the relay will be in the off state. When the water content is less than the required level then the soil will become dry this will activate the circuit and the 555 timer IC will send a high signal to the relay for a preset time so any pump connected with the relay will be switched on.
The preset time of the activation of the relay can be changed by adjusting the 1M variable resistor or it can be further increased by increasing the value of the capacitor Cx. The sensitivity of the probes depends on the 50K variable resistor, you can adjust this variable resistor to switch the relay and pump on at the desired dryness of the soil.
