329 – External Light Sensor

The 329 DALI External Light Sensor enables Open Loop Constant Light Control.

Mounted outdoors, the information that it gathers can be used to control general lighting levels.

For instance, bright sunlight will raise the overall light level in the rooms of a building. The sensor will detect this, and reduce the energy levels supplied to the lamps. If the day then becomes overcast, the system will respond to the lower levels of ambient light by increasing the energy provided to the lamps. By profiling the building (measuring the daylight contribution per room) the system can be used to maintain an approximate constant light level, and thereby reduce energy use.

Light Sensing Angle

The sensor has an unrestricted viewing angle of 170°.

Light Level Output

The external light sensor is calibrated to provide a scaled light level output of 0 lx to 200 lx covering the full range of daylight.

The sensitivity of the external light sensor is factory-set and no adjustment is required.

Tips:

When accurate constant light is required use local sensors and Closed Loop Constant Light control; see Working with Constant Light.

At midday, typically areas closest to windows are around 1/10 of the daylight measurement and moving away from the window quickly falls to around 1/100.

Related Topics

• Open Loop Constant Light Configuration

• Open Loop Scene Recall Configuration

• 311 Ceiling PIR Detector

• 312 Multisensor Module

• 315 iDim Sense

• IR Remote Control Receiver

• Constant Light Sensor

• Properties

• Devices View