Not every LED lamp is dimmable. Even with suitable versions, the dimming properties are very different and depend on the manufacturer. LEDs frequently flicker and cannot be dimmed linearly and harmonically, as the required electronic ballasts react with great differences to the leading and trailing edge. This is why some manufacturers only explicitly allow one of the methods.
Another problem is caused by the interference suppression capacitors of the dimmer. Continuous very low residual currents run through them. These are sufficient to supply LED lamps with one or two watts of rated output. Then they no longer go out completely. A similar effect can be caused by long lines positioned in parallel.
For a stepless control, not only do the LED lamps have to be dimmable, but also the dimmer must be LED capable. Theben has developed several solutions for this purpose:
– Presets for different LED lamps
– Dimming curves that can be reloaded via the ETS
LED compatible switching devices from Theben, such as the universal dimmer DIMAX 534 plus, offer additional setting options for a perfect adaptation to this technology. A minimum brightness for LED lamps with low wattage can be set using potentiometers and rotary switches. Even the type of control, phase angle or trailing-edge phase control can be preselected. This practically allows all dimmable LED lamps of renowned manufacturers to be controlled reliably.
KNX universal dimmer actuators from Theben go one step further: in the KNX programming software ETS, various dimming curves are stored, which correct the dimming response depending on the lamp used, thus ensuring stepless transitional dimming. Another advantage of the new dimming actuators is the extensibility of the dimming curves. New dimming curves, e.g. for future lamps, can be conveniently imported via ETS. With this update capability, KNX dimming actuators ensure your investments are well-protected.