The PWM output frequency can be flexibly adjusted by the user via the application software and set up to 4 kHz. The high PWM frequency eliminates risks related to flicker, which are evaluated in IEEE 1789-2015. The human eye does not perceive changes in light levels linearly, leading to a difference between measured and perceived light levels. For this reason, three freely selectable dimming curves are available: linear, DALI, and logarithmic. The lowest dimmable light level of 0.01% over the logarithmic curve corresponds to 1% perceived light. This enables applications where very low luminance is required, such as in cinemas. In applications where power requirements and dimensions allow, it is advisable to use an LED power supply with a KNX interface directly, to avoid additional dimming actuators or gateways. The power supplies of the PWM-KN series have a wide input voltage range of 90 to 305 VAC. Thanks to the high efficiency of up to 90% and the fanless design, the entire series is capable of operating at ambient temperatures from -40 °C to +90 °C under free air convection. The PWM-60KN series power supplies from MEAN WELL are available with output voltages of 12 V and 24 V.