| Word | Description |
| Occupancy sensor switch | Occupancy sensors provide on/off control of light sources where energy management is critical. They generally incorporate two types of technology to trigger lighting fixtures: infrared and ultrasonic. Infrared sensors create a field of energy in a pattern of beams to cover a specified area. The drawback is that they require an unobstructed line of site over the area being controlled to be most efficient. On the other hand, ultrasonic sensors fill a room or area with inaudible sound, “seeing” over partitions and obstructions. The drawback to this device is that it can be too sensitive to disturbances that may occur outside its field. Current occupancy sensing devices incorporate both technologies, balancing their strengths and weaknesses in a reliable product. |