Constant Lighting Control


Constant light control is used to regulate the 'clarity' lux in a room. The goal is to ensure that the lux value for the room stays the same. The lux will vary over time in a room in case external light can enter the room, for example sun light coming in through the window.
Lux is the unit to measure the intensity, as perceived by the human eye, of light that hits or passes through a surface.



Enter a short and clear name for the 'constant light control function’ here.


Default target
The amount of lux that the measurement from the light sensor should have.
Light sensor
The sensor used to measure the amount of lux in the room.
Single area, multi area. Single area is used when the room size is rather limited. So that it does not matter where we are in the room the clarity will be more or less the same. Multi area is used when we have a big room and that the further we are from the external light source (sun light coming in through the window) we will notice a real difference in clarity.

Select light brightest area

This section is used to to configure the dimmer(s) used for the room.

Single area

Select light source: the following light source types can be selected or regulate the lux. Dimmers, tunable white, dimmable local mood.

Multi area

Select light source: the following light source types can be selected or regulate the lux. Dimmers, tunable white, dimmable local mood.

Correction point
compensation performed in respect to the reference area (conversion point). A negative value will under compensate the dimmer. Used for spaces in the room where it will be brighter then where the clearity is measured. For example near the window. A positive value will over compensate the dimmer. Used for spaces in the room where it will be darker then where the clarity is measured. For example at the back of the room.
Convergion point
The point where no correction is performed any more. This area is also considered as the reference area.

The correction mechanimse is base on a convex kite.
For example if we have -20%(correction), 80% (convergion), +20%(correction) we would get the following sample values for a given reference point.

1% reference: 0% for -20% correction area, 1% for the convergion area, 21% for +20% correction area.
40% reference: 30% for -20% correction area,40% for convergion area, 50% for +20% correction area.
80% reference: 80% for -20% correction area,80% for convergion area, 80% for +20% correction area.




General delay time
the general delay time is used to turn the dimmers off again or go to safety, after the last motion trigger.

This can be seen as a motion window(time frame), and in that time frame the CLC will regulate the light to the given target. Each time a new motion trigger comes in then that window will be reset 'prolonged'.
A special case is a general delay time of 0 seconds. This can be used when you don't need a motion trigger, but want the CLC to be started simply by turning on the function (from a local mood, for instance) and stopped (i.e. by turning off all dimmers) when you turn off the function. This can be useful in showrooms or stores for instance, where an area must be well-lit constantly, even when there is no motion.

CLC function always ON
The CLC can not be switched off or on by a button or mood, it will always be on an and waiting for motion triggers to start running.
CLC function to OFF after general delay time
used to not only switch the lights off but the CLC function as well after motion window has expired. In this case a person must explicitly switch the CLC back to ON.
PID control
Normal, Slow and fast. This parameter is used to determin how fast the CLC needs to react on light changes.


This is used to change the length of the motion window (time frame) in witch the CLC will regulate the light.
This is used in cases where we know that people will just pass by the area instead of being present for a long time. So we want the period of operation shorter then in the case that there are people present.

check in case we want to use the walk-through option.
Detection time
The amount of time that we say that it is not a walkthrough any more but a normal case of people present in the area. so if we specifies 20 seconds that means that if we get motion triggers after 20 seconds in walkthrough we will say that it is a case that the person is present in the area and is going to stay. This will result in the fact that the CLC window will have the length of the general delay time.
Delay time
same function as the general delay time. but we expect that it will be setted shorter then the general delay time(not a hard requirement).

Safety mode

Used to change the CLC target after the CLC window has expired. So when this is turned on the CLC will regulate to new target after the CLC window (motion) has expired. In case we get a motion trigger when the safety is running the CLC will go back to the walkthrough if configured or the general delay time in case the walkthrough was not configured.

check in case we want to use the safety mode. by default this means that the light will never be switched off by the CLC.
Standby target
The amount of lux that the measurement from the light sensor should have. This will normally be less then when people are active in the area.
Switch lights to OFF after delay time
check when we want to switch lights off
Standby delay time
The CLC window (safety) for witch the CLC will operate for the given standby target.


A constant light control function can be configured behind a button, local mood or motion detector. The later is used to trigger the constant light control.

Clc target, CLC function ON/OFF, Motion detect. Clc target is used to change the target lux for the CLC. This could be used in case that in a room different activities are taking place over time. Because for some activities we want more or less clarity.

CLC function ON/OFF is used to turn the CLC function ON or OFF. Note that when always ON is configured the OFF action will be ignored. Motion detect is used to indicate that motion occured. This will usually be configured for inputs that have a motion sensor attached to it.

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