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This Arduino-based night security light can protect your home/office from thieves/intruders at night. The light glows when movement is detected in front of the PIR sensor. Simultaneously, a piezo buzzer also sounds.
Features of the Night Security Light System:
- Automatic Activation: The light turns on when it’s dark and motion is detected by the PIR sensor.
- Duration Control: Upon detecting movement, the light remains on for ten seconds. If motion is detected again within this time, the countdown restarts.
- Daylight Sensing: The system remains off during daylight even if motion is detected.
- Incorporation of a Piezo Buzzer: A piezo buzzer sounds simultaneously with the light to alert during intrusions.
Video Tutorial In English
Video Tutorial In Tamil
The prototype of the Arduino-based night security light system is shown in Fig. 1.

Components Required | |
Semiconductors: | |
– BC547 NPN transistor | – Arduino board |
D1 | – 1N4007 rectifier diode |
Resistors (all 1/4-watt, ±5% carbon): | |
R1 | – 10-kilo-ohm |
R2-R3 | – 1-kilo-ohm |
T1, T2 | – BC547 NPN transistor |
Miscellaneous: | |
CON1, CON3, | |
CON4 | – 2-pin connector |
CON2 | – 3-pin connector for PIR |
PZ1 | – Piezo buzzer |
– PIR motion sensor | |
– LDR | |
– Breadboard | |
– Jumper wires | |
– 12V, 1C/O relay | |
– 60W, 20V AC bulb |