Hue Brightness Sensor

The Hue brightness sensor is available as a technical unit with the temperature and presence sensor under the name "Hue Motion Sensor" from Philips. The module referred to here as a brightness sensor can measure the current ambient brightness. The currently measured brightness value is converted into the boolean values ​​"dark" and "bright daylight" according to the configured parameters. For the conversion of the measured brightness value from 0 to infinity (not candela (cd) and not lumen (lm), but a quantity defined by Philips) into the two boolean values ​​"dark" and "bright daylight" the following parameters are used:

  • Threshold for detecting darkness (darkness threshold): If the brightness value is below the darkness threshold, "dark" is detected. If the brightness value is above the darkness threshold, "Not dark" is recognized.
  • Threshold value for detecting bright daylight (brightness offset): If the brightness value is below the darkness threshold + brightness offset, "bright daylight" is detected. If the brightness value is above the darkness threshold + brightness offset, "bright daylight" is recognized. The brightness offset parameter is therefore a threshold value that is defined relative to the dark threshold.

The following example should clarify the behavior: The dark threshold is set to 16000, the brightness offset is defined as 7000. This results in the following three areas:

Brightness value Boolean flag "Dark" Boolean flag "Bright daylight" Meaning regarding brightness
less than 16000 true not true Darkness
16000 to 23000 (23000 = 16000 + 7000) not true not true Few daylight
greater than 23000 (23000 = 16000 + 7000) not true true Sunshine

In order to be able to react to the brightness range from 16000 to 23000 ("few daylight") in the above example, two conditions must be used, namely "Not dark" and "Not bright daylight".

The functions of the Hue motion sensor, i.e. the reaction to the states described above (e.g. to switch on a group of lights), are not made in the settings of the Hue brightness sensor, but by creating corresponding rules.

Settings

The following parameters can be adjusted with this app:

  • Description of the sensor
  • Threshold for detecting darkness: Dark threshold (see above for details)
  • Threshold for detecting bright daylight: Brightness offset (see above for details)