Use Objects For Brightness Adjustment - Busch-Jaeger mini KNX 6131/20 series Technical Manual

Use objects for brightness adjustment

There is the option of carrying out a brightness adjustment for daylight and artificial light via the
brightness detection application with the aid of the following three objects:
(a) Brightness adjustment (daylight)
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(b) Brightness adjustment (output 1)
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(c) Brightness adjustment (output 2)
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In the event that artificial light and daylight are perceived similarly by the sensor, or the
movement detector application is used exclusively, only the absolute brightness value need be
corrected. For this the brightness value can be sent via the brightness adjustment object
(daylight), which is to be displayed by the actual brightness measured by the device. This is
then used to internally calculate a correcting factor, which will then be used for scaling /
adjusting the internally measured brightness. This adjustment is sufficient for the movement
detector application. For constant light controller and switch further step may be necessary,
which are described in the following.
For the event that daylight and artificial light must be corrected separately, the following
procedure is recommended:
(a) Daylight adjustment
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– Perform the measurement during sufficient daylight (> 1/2 * setpoint)
– Switch off the artificial light
– Carry out the measurement of brightness at a defined location with a luxmeter - for
example, lying down at the workplace with a view toward the ceiling - and wait until the
light is close to being constant. Send the value to the device using the brightness
adjustment (daylight) object. As little time as possible should pass between measuring
and sending, to keep the probability of a change in light conditions at a minimum.
(b) Adjustment for channel 1
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– Darken the room
– Switch on channel 1 (max. brightness) and wait until the brightness is virtually constant.
– Measure the brightness with the luxmeter as previously. Send the value to the device
via the "Brightness adjustment" object (output 1).
(c) Adjustment for channel 2
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– Repeat M-measurment (b) for channel 2. Switch off channel 1.
KNX Technical Manual 2CKA001473B8667 │ 06.02.2017
Commissioning
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