ABB i-bus KNX Product Manual page 69

®
ABB i-bus KNX
© 2008 ABB STOTZ-KONTAKT GmbH
Commissioning
Switch off if control deviation is greater than [0...30]
Options: 0/1/2...5...29/30
When the lower control limit is reached the Light Controller normally
switches off the lighting immediately. This avoids abrupt changes in
the brightness or in certain circumstances that the lighting is switched
back on immediately. In order to avoid continuous switch on and off of
the lighting a divergence can be parameterised with this parameter.
The Light Controller maintains the minimum control limit until the
calculated setpoint deviation has exceeded the parameterised value.
Only then is the lighting switched off.
This ensures that the existing brightness level is so high during switch
off so that the Light Controller does not immediately switch the lighting
back on.
The Light Controller calculates the divergence from the current sensor
value of the Light Sensor and the brightness which would result in
switching on the artificial lighting. This artificial lighting brightness
level has been automatically recorded and saved during artificial
lighting calibration of the Light Sensor.
Note
The Light Controller can automatically switch off the luminaries
when the lower control limit is reached. Before the Light Controller
switches off the illumination, it determines if the brightness in the
room is sufficiently high enough so that the required setpoint will
not be reached when the lighting is switched off. For this purpose,
the measured actual value of the artificial lighting share of the lower
limit and the value of the parameter Switch off if control deviation is
greater than are subtracted. If the difference is greater than the
setpoint, the Light Controller switches off the lighting.
The artificial lighting share is determined by the Light Controller
during implementation of the artificial and daylight calibration.
Compensation factor for daylight calibration automatically
Options: no
yes
With this parameter the factor for the daylight compensation can be entered
manually in the ETS. This factor considers the evaluation of the artificial
lighting and the natural incidence of light using the Light Sensor. Generally
this factor is determined automatically by the Light Controller during the
daylight calibration, refer to
lighting control.
•
no: This should be selected if no daylight calibration is to be performed,
e.g. the natural brightness is not sufficient or no shading possibilities are
available to set the setpoint during daylight. Both parameters are
enabled:
Commissioning/calibration of the constant
67