Dual-Loop Photosensor Control System for Daylight Harvesting

Dual-Loop Photosensor Control System for Daylight Harvesting
Publication Date: 
03/01/2013

To maximize the respective benefits of open-loop and closed-loop systems, and minimize their limitations, the California Lighting Technology Center (CLTC) developed a dual-loop photosensor control system for skylight applications. The system features a control algorithm that monitors the open-loop and closed-loop photosensors and controls the electric light to provide the designed light level. It also automatically recalibrates nightly in order to adjust to longterm changes to the interior space.

Features & Benefits:

  • Automatic recalibration reduces maintenance costs
  • Differentiates between daylight and space changes for more accurate light level adjustments
  • Dramatically improves lighting consistency
  • Improves the energy savings of open-loop control systems by 50%