Today’s Sensors Bring New Savings to Light
Chuck Ross
Occupancy sensors are quickly becoming a regulatory requirement in many commercial spaces, thanks to evolving energy codes seeking to wring out kilowatt-hours of energy savings anywhere it’s possible. Of course, these devices have been around for decades, but manufacturers have introduced new innovations over the last decade to both improve installation and ease the programing required to set sensors for time delays and other parameters.
Most sensors today operate using passive infrared (PIR) designs, a technology that helped drive adoption since it was introduced back in the 1970s. “PIR sensors detect changes in the infrared energy given off by occupants as the move within the field-of-vision of the sensor,” explains Nicole Sanborn, marketing manager for Acuity Brands, a leader in lighting controls. “The sensor ‘sees’ the heat given off by the human body as it moves and triggers the occupancy mode. The sensors are fine-tuned to detect small motions, even at great distances, while still preventing false triggers.”
Placement remains a bit of an issue with PIR sensors, though, because they require line-of-sight positioning with regards to any possible occupants. That’s one reason why these products are marketed in several different form factors, both as part of a traditional light switch and in half-dome designs for ceiling mounting. The switches work well in open spaces, like private offices, break rooms and bathrooms, while ceiling-mount versions will perform better in settings where cubicles or other barriers could obstruct the sensors’ ability to detect human occupants. Some products add microphonics technology as a backup detection option. This approach uses an internal microphone to detect sounds that indicate continued occupancy, so lights stay on even if you fall out of that direct line-of-sight.
Installers and facilities staff now have new ways to interact with settings for things like how long lights should stay on after occupancy is no longer detected. In the past, this involved adjusting physical pins within the sensor. Now, mobile device apps have taken over this task. Using either Bluetooth communications or programs that communicate with the sensor using a phone’s camera flash – a technology called visible light programing. These advances can be especially helpful in speeding up commissioning for larger, multi-switch installation projects.
Most sensors today operate using passive infrared (PIR) designs, a technology that helped drive adoption since it was introduced back in the 1970s. “PIR sensors detect changes in the infrared energy given off by occupants as the move within the field-of-vision of the sensor,” explains Nicole Sanborn, marketing manager for Acuity Brands, a leader in lighting controls. “The sensor ‘sees’ the heat given off by the human body as it moves and triggers the occupancy mode. The sensors are fine-tuned to detect small motions, even at great distances, while still preventing false triggers.”
Placement remains a bit of an issue with PIR sensors, though, because they require line-of-sight positioning with regards to any possible occupants. That’s one reason why these products are marketed in several different form factors, both as part of a traditional light switch and in half-dome designs for ceiling mounting. The switches work well in open spaces, like private offices, break rooms and bathrooms, while ceiling-mount versions will perform better in settings where cubicles or other barriers could obstruct the sensors’ ability to detect human occupants. Some products add microphonics technology as a backup detection option. This approach uses an internal microphone to detect sounds that indicate continued occupancy, so lights stay on even if you fall out of that direct line-of-sight.
Installers and facilities staff now have new ways to interact with settings for things like how long lights should stay on after occupancy is no longer detected. In the past, this involved adjusting physical pins within the sensor. Now, mobile device apps have taken over this task. Using either Bluetooth communications or programs that communicate with the sensor using a phone’s camera flash – a technology called visible light programing. These advances can be especially helpful in speeding up commissioning for larger, multi-switch installation projects.
Photo courtesy of Acuity Brands
