The ABB i-bus® light sensor LF/U 2.1 is a brightness sensor for closed rooms.
The light sensor is mounted in a standard installation box in the ceiling.
The cover (white) of the sensor is stuck firmly onto the device. The complete unit is then screwed into a flush-type box.
On the Light Controller LR/S x.16.1 (x = 2 or 4) up to 2 or 4 Light Sensors LF/U 2.1 can be connected. The light sensor measures brightness values in closed rooms. When combined with the detected values, the Light Controller is
used for constant light control. It is possible to combine the brightness values from several Light Sensors for the calculation of an individual control circuit.
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