Guide to Choosing LED Dimmers

Dimming LED lighting can sometimes be quite challenging. In some cases, you may experience flickering lights, buzzing dimmers, humming lamps, incompatible cover plates, and other minor issues. In this blog, we explain what to consider when dimming LED lamps so you can be well-prepared.

Is Your Lighting Dimmable?

Not all (LED) lighting is dimmable. You can usually check this by looking for a symbol, logo, or text on the packaging. If it is not explicitly stated that the lamp is dimmable, then it is not dimmable. LED lamps are not dimmable by default. If you try to dim a non-dimmable lamp, it will start flickering immediately and may stop working in no time—what a waste!

12V or 230V LED Lamps?

Most lamps operate directly on 230V, which is the standard voltage that comes from a power socket. The most common 230V lamps include E14 (small screw base), E27 (large screw base), and GU10 bulbs. These 230V LED lamps can usually be replaced one-to-one. If they are dimmable, they can be connected directly to a dimmer.

Some lamps operate on 12V, such as G4, MR16, or MR11 spotlights. If you want to dim these lamps (assuming they are dimmable), the transformer is crucial. A halogen transformer, for example, operates with a ballast of 30-500W, which is usually indicated on the transformer itself. Because LED lighting is so energy-efficient, its power consumption often falls below the minimum ballast of 30W. As a result, these LED lamps cannot be dimmed with a standard halogen transformer. If you want to dim these types of LED lamps, you need a special dimmable LED transformer.

Use an LED Dimmer

As mentioned earlier, the minimum load capacity of the dimmer is crucial. This is why LED lamps usually cannot be dimmed with a halogen dimmer, as these dimmers typically have a minimum power requirement of around 40 to 60 watts. The average LED lamp has a much lower power consumption, meaning a halogen dimmer will either fail to dim the LED lamp properly or cause it to hum or flicker. To avoid this, choose a specific LED dimmer, which usually has a load range of 0-150W or 0-450W. This ensures that even low-power dimmable LED lamps can be dimmed effectively.

Leading-Edge and Trailing-Edge Dimming

LED dimming works in two ways: leading-edge dimming and trailing-edge dimming. Dimmer compatibility is usually indicated with RL (leading-edge), RC (trailing-edge), or RLC (both leading- and trailing-edge).

The driver inside the lamp determines whether it works with leading-edge or trailing-edge dimming. While the technical details may not be essential, choosing a compatible dimmer is crucial. An incorrect dimmer can cause flickering, buzzing, or failure to dim. Most lamps specify the required dimming technology on the packaging. If this is not stated, trailing-edge dimmers are the safer choice—about 90% of LED lamps work best with trailing-edge dimming. Alternatively, universal (RLC) LED dimmers support both dimming methods, ensuring compatibility with almost any lamp.

Still unsure which dimmer suits your lamp? Feel free to contact us! We’re happy to help you find the best solution.

Load Capacity and Ballast

If you plan to connect multiple lamps to one dimmer, it is best to use lamps of the same type. Avoid mixing LED and halogen lamps on the same dimmer. Also, using lamps with the same wattage ensures a consistent and stable dimming experience.

Check the load capacity of the dimmer before purchasing. Many dimmers specify two different load capacities—one for LED lamps and one for halogen lamps. Generally, the halogen load capacity is higher than that of LED lamps. For example, a dimmer may support 5-85W of LED power and 10-350W of halogen power. The EcoDim dimmers we sell in our webshop always indicate LED load capacity because they are specifically designed for LED lighting. Depending on the model, these dimmers range from 0-150W or 0-450W.

The Right Dimmer, but the Lamps Still Flicker

If you've checked everything above but your lamps still flicker, the issue is often the low or high light level settings. The LED drivers may receive too much or too little input. If the lamps don’t have built-in adjustment settings, this issue can be difficult to resolve. However, a dim stabiliser can often fix it. This device should be installed before the LED lamps.

Most EcoDim dimmers include a min-max regulator, allowing you to adjust the low and high light levels manually. If your LED lamp flickers at low brightness, increasing the minimum setting can solve the issue. This provides the dimmer with more power, stopping the flickering. The dimmer then “remembers” this lowest brightness level, preventing flickering when you turn the lamp on and off. The same principle applies to adjusting the maximum brightness.

Cover Plates

Once your dimmer is correctly installed and working perfectly, the final step is choosing the right cover plate. Ensure that your new dimmer is compatible with the cover plates you already have, as compatibility can vary. EcoDim dimmers are designed to fit most popular cover plate brands.

Now you’re fully informed about what to consider when purchasing and installing a dimmer. Still have questions or need help choosing the right dimmer for your lamp? Feel free to contact us! The Qub lighting experts are happy to assist you in finding the perfect solution.