Occupancy Motion Sensors
Lighting can account for 20% of energy use in a building with high activity. This is when energy savings becomes very important to business owners. Simply adding lighting controls to your existing lighting application can easily reduce that portion by 25%. Occupancy sensors are a standard means for saving energy, increasing security, extending lamp life, and decreasing maintenance costs.
Many occupancy sensors use Passive Infra-Red (PIR) as they are best for detecting major activity like an occupant walking through a space. This sensor works by detecting movement of heat sources in its direct range of view. Many of the newer sensors, such as the ones offered on our site, have a 180 degree range of detection and an ultra-efficient LED light source and optical design.
Ultrasonic technology in occupancy sensors is perfect for the detection of minor movements, such as typing at a computer for an extended period of time. Ultrasonic sensors work by releasing a pulse into a space. The pulse reads differently when it ricochets back if there is movement in the area.
Vacancy Sensors – What’s The Difference?
Vacancy sensors will monitor your space to turn lights off if vacancy is detected for an indicated length of time. It has been shown that energy use decreases when we control our lighting needs and access to daylight when needed. Using standard occupancy sensors that are set to “automatically on” is perfect for spaces with little natural light. If your space has a lot of natural daylight a vacancy sensor may be preferable.
Sensor placement—open offices
Open offices are often large areas with cubical walls of varying heights, with light fixtures, air returns, sprinklers, and other devices on the ceilings—all of which you’ll need to take into account. Another important thing to note is that it’s not usually necessary to have occupancy sensor coverage on every square inch of space in an open office, simply because these spaces generally have many people moving around in them.
• Cover the main walkways.
• Make sure that the coverage patterns overlap on the walkways. This is important for ensuring that there aren’t blind spots where people might walk around but not trigger the occupancy sensor.
• Use a longer timeout (15 or 30 minutes).
• Use ceiling-mounted sensors; if the cube walls are short you might also want to use wall mounted sensors.
• Avoid mounting sensors close to air vents, as the vibration and air flow can reduce the effectiveness of the sensor (PIR sensors should not be within 4ft of an air vent, and ultrasonic sensors should not be within 6ft of an air vent).