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An occupancy sensor detects whether a room or zone is occupied. When nobody is detected, the building management system dims the lights and adjusts the heating setpoint. A large commercial office fitted with occupancy sensors across all its meeting rooms and open-plan areas stops conditioning spaces that nobody is using.
Technologies range from passive infrared (detects body heat movement) to AI camera-based counting (most accurate, tracks individuals). LoRaWAN sensors connect wirelessly over long ranges without adding to the building’s electrical infrastructure.
- PIR (Passive Infrared) – detects movement of warm bodies, simple and low-cost, misses completely still people
- Ultrasonic – detects movement via sound reflection, better at detecting seated people
- Microwave/radar – detects movement through partitions, useful for full zone coverage
- AI camera-based – directional counting, occupancy totals, real-time zone loads; most accurate