Multiple awards: Design prizes for thePrema
For its aesthetic design, thePrema has won several awards.
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Technology: How does a presence detector work?
Presence detectors work according to the same principle as motion detectors: They detect thermal radiation in their surrounding, that is in their detection area. If thermal radiation is detected in the detection area, for example caused by a person approaching the presence detector, the presence detector converts the radiation into a measureable, electric signal, and the light is switched on.
Sensors in the detection area
The difference between motion and presence detectors lies in the sensitivity of the sensors. Presence detectors have far more sensitive sensors than motion detectors and detect even the smallest of movements.The sensitive sensors divide the detectionarea of a presence detector evenly into upto 1000 zones. Like a chessboard, the zones run through the entire detection area. Even minimum changes in the thermal image, such as typing on the keyboard in an openplan office, will be detected. In contrast, a motion detector only responds to greater changes in the thermal image and is therefore mainly suited for applications with larger, walking movements or outdoor use.
Light measurement with presence detectors:
A further difference between motion and presence detectors lies in the light measurement. A motion detector measures brightness once, when the light is switched on because of a movement. If it continues to detect movements, e.g. in the morning in an office, the light remains switched on although daylight would be sufficient in the meantime and the set brightness value has already been exceeded. The light unnecessarily remains switched on. In contrast, presence detectors permanently measure the brightness: If an individually set brightness value is exceeded, the presence detector switches the light off, even if it detects movement. That saves energy costs and a large amount of CO2