ABB i-bus KNX Product Manual page 127

®
ABB i-bus KNX
© 2008 ABB STOTZ-KONTAKT GmbH
Planning and application
Automatic implementation of daylight calibration
The sequence of daylight and artificial lighting calibration is not random.
Calibration with artificial light must be performed before calibration with
daylight.
The daylight calibration can be undertaken automatically by the Light
Controller or experimentally by the user. The required setting can be found
in the parameter window
for daylight calibration automatically. Automatic calibration is preferred.
The artificial lighting should be turned off for daylight calibration.
The same brightness level (setpoint) as artificial lighting can generally be
created using shading units. In order to prevent with a high level of certainty
that the setpoint is not undershot in the controlled state, a brightness can be
set for the daylight brightness which is about 10 % above the brightness
value of artificial brightness calibration.
Via the object Enable calibration it is recommended that the readiness to
receive of the object Calibration daylight is undertaken. The calibration can
be undertaken by a telegram with value 1 sent to the object Calibration
daylight. The Light Controller undertakes the calibration and determines
the levels (weighting) of artificial lighting and daylight. After this calibration
the Light Controller switches the setpoint and commences with lighting
control. When the daylight calibration has ended the value of the object
Calibration daylight is set again to 0. The T flag should be set beforehand.
The value can be read as an alternative. At the start of daylight calibration
the value of the object Enable calibration (25) can be detected. At the start of
daylight calibration this object value is set to 0 by the Light Controller.
If a shading device is not available for use or the daylight is not sufficient,
a manual daylight calibration can be undertaken.
X: Control with the parameter Compensation factor
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