Introduction
In cold climates, people wear heavy clothing that insulates body heat. This can reduce the infrared signal reaching the PIR sensor, making detection difficult.
Why Heavy Clothing Affects Detection
PIR sensors detect the infrared radiation emitted by a person’s skin and clothing. Heavy, insulated clothing:
- Blocks body heat from reaching the surface.
- The outer surface of the clothing may be near ambient temperature.
- Reduces the temperature difference between person and background.
Symptoms
- Sensor detects people in summer but not in winter.
- People wearing heavy coats are not detected until very close.
- Detection range decreases in cold weather.
Solutions
- Increase sensitivity (turn potentiometer to maximum).
- Use a more sensitive sensor (Panasonic EKMB series).
- Use a sensor with better low-temperature performance.
- Use a different technology (microwave or mmWave radar).
Conclusion
Heavy clothing reduces PIR effectiveness. In cold climates, consider alternative technologies or combine with other sensor types.