Photometric Parameters of LED Luminaires with Switchable Correlated Colour Temperature

At present, there are lights on the market that are capable of emitting white light with an adjustable correlated color temperature. The advantage of these luminaires is the possibility of changing the correlated color temperature, for example, due to a change in the function of the room in which they are installed, with no replacement of the lamps. The disadvantage of such a correlated color temperature setting is that this setting is performed directly on the luminaire and it is not possible to set the correlated color temperature with the control system. When changing the color temperature, in most cases, it is undesirable to change the other photometric parameters. In this paper, attention is paid to changes of the photometric parameters caused by changing the correlated color temperature.