This is one of the simplest DIY projects of an Automatic Lamp circuit/Dark Activated 230V Lamp Circuit. It is only using five components and can be used for automatic activation of an AC lamp/bulb when the sun sets or when there is dark around the circuit.
This circuit is taking input from AC mains voltage which has the possibility of giving you a lethal shock if not careful. So, if you are a beginner and don’t know much about working with AC line voltages do not attempt to construct this circuit.
Hardware Components
The following components are required to make an Automatic Night Lamp Circuit
| S.no | Component | Value | Qty |
|---|---|---|---|
| 1. | AC Supply | 230V | |
| 2. | Diode | 1N4007 | 1 |
| 3. | Variable Resistor | 4.7M | 1 |
| 4. | LDR | – | 1 |
| 5. | SCR | 2P4M | 1 |
| 6. | Lamp | 230V | 1 |
| 7. | Breadboard | – | 1 |
| 8. | Wires | – |
2P4M Pinout
For a detailed description of pinout, dimension features, and specifications download the datasheet of 2P4M
Automatic Night Lamp Circuit
Working Explanation
The input of 230V is coming from an AC mains supply. 4.7M variable resistor is used to adjust the sensitivity of this circuit, you can adjust the amount of dark on which you want your Lamp to turn ON.
LDR is connected in this circuit in such a way that when there is light present around the circuit the resistance of LDR will be minimum and the voltage will be sent to the ground therefore Lamp will remain switched OFF. When LDR senses dark its resistance maximizes and it will stop the current from going to the ground, that current will be fed into the SCR and it will switch ON which eventually activates our Lamp/Bulb by providing it the 230V AC.
Applications and Uses
- Emergency Light
- Bedside Lamp
- Bulbs or Lights for houses
- Decorative purposes
