ABB i-bus KNX Product Manual page 65

®
ABB i-bus KNX
© 2008 ABB STOTZ-KONTAKT GmbH
Commissioning
Daylight calibration
Control
active/inactive
Master/slave
operation
With daylight calibration the Light Controller determines
the actual value which produces the required setpoint
without artificial lighting. In this way the Light Controller
determines the different influences of artificial lighting and
natural incidence of light on the Light sensor. The daylight
calibration should be performed without the influence of
artificial lighting. This should be set by the change of
shading of the setpoint brightness value on the reference
point in the room. If this is not possible the daylight
calibration can be assigned with a predefined factor via
the ETS. By observing the control behaviour this factor,
it should be optimised empirically so that the light control
is set as exactly as possible to the target brightness level.
For further information see: Constant lighting control
The sequence of daylight and artificial light calibration is
not in any desired order. Calibration with artificial light
must be performed before calibration with daylight.
At any time the user can operate the light control with
appropriate parameterisation using normal dimming
commands, e.g. interrupt dimming, switching or scene
recall in order to operate the lighting manually according to
their requirements. The Light Controller is in standby mode
and recommences with light control via an ON command,
e.g. telegram with the value 1 on object Switch.
The "actual" deactivation of the light control is
implemented via the object activate control. With inactive
light control the Light Controller acts like a normal
Switch/Dim actuator. Switch commands are implemented
without light control being active. Light control is only
restarted if on object activate control a telegram with the
value 1 is received.
If the light control is activated it can be recognised using
the first bit of the status byte.
The general object Status function indicates if the light
control actually controls, i.e. the Light Controller
continuously performs a setpoint/actual comparison.
The control value for the illumination is provided
dependent on the control difference.
It is possible that a Light Controller also controls other
dimming actuators. In this case the Light Controller
(Master) also controls other Dimming Actuators (slaves)
via the object Brightness value of slave or other channels
internally directly in the LR/S.
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