Can you dim LEDs? Technically, this is not a problem; however: Only explicitly as dimmable LED lamps marked bulbs and lights can be dimmed! Since the interface between dimmer and the LED lamp is not standardized, not every LED dimmer will work with each LED lamp. Also, the minimum base load of the LED dimmer must be less than or equal to the power consumption of the connected light.
For multiple LEDs operated with a dimmer, the LED dimmer must align with the lowest power lamp; Similarly, the maximum permissible load of the dimmer must not be exceeded, so that a uniform light result is achieved.
Caution: Using a dimmer with an LED lamp that is not marked as dimmable can cause it to flicker or even break. If you use a dimmable LED with an incompatible dimmer, dimming the LED, if at all, will be very limited and will damage the bulb.
LED flickers when dimming – what can I do?
Flickering when dimming can have different causes. On the one hand, as already indicated above, it can be due to the LED itself: If this is not marked as dimmable, you should also not use the light source with a dimmer. On the other hand, it can also be due to the dimmer: This should be suitable for LED lamps.
These possible causes are associated with the allowable load of the dimmer: The dimmer is designed for a light source that is within the range of a given wattage. Accordingly, the illuminant should be cut to the appropriate area indicated on the dimmer.
Most old dimmers do not work with LED bulbs.
So-called universal dimmers, which have been developed for light bulbs or halogen lamps, are generally not compatible with LEDs because they have a higher minimum load. Light-emitting diodes, on the other hand, consume hardly any current, starting only at a specific forward voltage of a few volts (1.2 V for infrared LEDs, up to 4 V for ultraviolet LEDs). Also, LED lamps operate on DC power and therefore require upstream electronics to convert the AC power from the grid. Dimmed is then, strictly speaking, not the LED light, but the interposed electronics.
Hardly uniform standards
The many manufacturers of LED lamps and dimmers have so far not been able to agree on a uniform control system so that when dimming LED lights, not only to the necessary technical data must pay attention, but also on the compatibility between the products of specific manufacturers. Therefore, the dimming of LED lamps remains a confusing issue, although the possibilities have improved significantly in recent years.
Recommendation: Avoid unnecessary annoyance by not buying the dimmer for LED lights unless you are 100% sure that it is compatible. If in doubt, it is worth asking the manufacturer of the lamp or the lamp, whether the selected model will work as desired; Many companies have compiled a list of LED dimmers recommended for their products.
Suitable dimmers for LED lights
In many LED dimmers is phase dimmer: In phases to cut dimmers, which are usually used for conventional transformers, the influence of the current waveform in the second part of a sine wave peak or -tails (this variant is carried out there for dimming LED lamps), in phases from cut dimmers (usually for electronic transformers) is reversed.
Besides these two technologies, which are also known from incandescent lamps, there is the method of pulse width modulation ( PWM ). Here, the current flow is interrupted periodically for a specified interval duration, whereby the LED lamp lights less bright. The longer the break, the stronger the dimming effect. For the human eye, the cracks are not directly visible because they follow each other too fast.
Another option is the DALI interface (Digital Addressable Lighting Interface), which allows various lamps throughout the house to be networked and controlled individually. In the meantime, it is technically possible to dim appropriately configured LED lights via a smartphone app; however, such products are still rare. The same applies to the digitally networked dimmer interfaces: only those who first get informed thoroughly buy dimmable LED lamps and dimmers that fit together well.
Various technologies are used in the dimming of LEDs, where the individual needs to be looked at, which is the right one. Therefore again, the hint: Inform yourself with open questions for each case exactly with the support of the manufacturer, to experience no unpleasant surprises. LEDs, at least, open up new possibilities for dimming, because not only the brightness but also the light color can be adjusted.