LF/U 2.1 ABB i-bus KNX Light Sensor Flush-Mount 200-3000 lx Brightness Probe for Constant Light Control

The ABB i-bus KNX LF/U 2.1 is a flush-mounted light sensor that measures illuminance levels in rooms and provides measured values to the KNX lighting control system. As the sensing element of ABB's constant light control concept, it works with light controllers LR/S 2.16.1, LR/S 4.16.1, or DALI light controller DLR/S with light controller module LR/M1.6.2 to maintain consistent, preset brightness levels. The sensor installs in ceilings facing the working plane and receives power through the light controller's connecting line.

• Device Type: Separate light sensor (brightness sensor for bus system)
• Measuring Range: 200 ... 3000 lx
• Compatible System: KNX TP1, wired to sensor input of light controller
• Color / Dimensions: White, 54 * 54 * 20 mm, 0.04 kg
• Ambient Temperature: -5 to +45 °C, IP20, flush mounting
• Certifications: CE Declaration of Conformity 2CDK507022D2701, CB certificate 9AKK107991A3197, RoHS 2011/65/EU, REACH (no SVHC above 0.1%), WEEE category 5
• ETIM 9: EC000927 - Brightness sensor for bus system

Ideal for open-plan offices, classrooms, corridors, and libraries to implement daylight harvesting. The controller dims 1-10 V ballasts as natural light increases and raises them as daylight decreases, maintaining designed lux levels at the working plane while reducing lighting energy consumption.