Occupancy Sensor

An occupancy sensor or vacancy sensor uses passive infrared, ultrasonic, microwave, or video image processing to detect the presence of a person in space. It is usually connected to the Internet of Things (IoT) network to automate processes related to booking, lighting, HVAC control, etc. It can also collect accurate and real-time data about space usage to optimize space management decisions.

There are three common sensor technologies that can detect occupancy.

Passive Infrared (PIR)
PIR sensors detect heat emitted by the human body and sense motion by measuring infrared (IR) light radiating from the object in its field of view. Therefore, they are usually suitable for small rooms. But sensors using PIR technology can be insensitive to objects in very slow motion.

Ultrasonic
Ultrasonic sensors emit a high-frequency signal and sense motion by a change in frequency. The frequency is high enough that it won’t be caught by the human ear. And it won’t be limited by line of sight, so these sensors will be suitable for larger spaces. However, change in temperature, airborne particles, weight, and air turbulence, can influence ultrasonic reaction, making it less accurate.

Microwave
Microwave sensors emit electromagnetic waves and analyze the reflected wave to detect occupancy. They can detect smaller motions so it is best for large offices and even outdoor use. Due to high sensitivity, they might also detect non-human presence like animals and fast-moving objects.

An occupancy sensor can provide real-time presence data of meeting rooms, desks, and open offices for the following applications.

Space Management Solution

Smart Office Solution

People Counting Sensor

Environmental Sensor

IoT