Which LED dimmer do you need for your spotlights?

You need an LED dimmer with a low minimum load, and the type has to match the driver in your fixture. An old halogen dimmer often needs 20 to 40 watts before it engages, and six LED spots never get there. That is where the flickering comes from.

Why your old dimmer has stopped working

A 40-watt halogen lamp drew enough current on its own to keep any dimmer stable. Replace it with LED and consumption drops by a factor of ten. A Lesto uses 4 or 6 watts, a Quaro 6 watts. Eight of those spots together come to about 48 watts — less than a single halogen lamp used to draw.

Your dimmer notices nothing, and that is exactly the problem. Below its minimum load it no longer knows where in the sine wave to switch. The light flickers, hums, or only comes on once you turn the knob halfway.

Two types of phase dimmer

A phase dimmer cuts a piece out of every half sine wave. Where it cuts determines the type:

• Leading edge (R.L., also called Triac) — the start of each half wave is cut off. This type comes from the halogen era.
• Trailing edge (R.C.) — the end is cut off. This is the type developed for LED, and the one most LED drivers can handle.

They are not interchangeable. A driver connected to the wrong type gives you flicker, buzzing, or a spot that drops out at half brightness.

Which dimmers we carry

Both of our dimmers are trailing edge. It is printed on the front of the unit as well, as R.C. with the matching symbol:

• LED dimmer 0.5-250W — with two-way switching, €21.95.
• LED dimmer 0.5-160W — with two-way switching, €24.95.

Both start at 0.5 watts. That is the more important half of the number: a single 4-watt spot sits well above it, so you do not need a minimum number of spots to keep the dimmer stable. In a home you will almost never reach the upper limit — at 6 watts per spot you could in theory hang forty spots on the 250W dimmer.

Both have a small screw for setting the minimum level, so your lamps do not flicker at their lowest setting. They fit behind most cover plates, so you can build them into your existing switch gear.

Check the driver in your fixture first

This is the step you should not skip, and it is on our product pages too: check whether the driver in your fixture supports this type of dimming.

For some of our spots the specifications state that a Triac dimmable driver is included — that is leading edge, so the other type. That applies to the Lesto and some versions of the Lesto 5W, among others. For other spots, such as the Lyvo, the Warmo, the Marlo and the Vigo, the specifications only mention a dimmable driver without naming the type.

If you are unsure about combining a particular spot with one of our dimmers, get in touch before you order. That is cheaper than a dimmer you cannot use.

Not every spot is dimmable

Dimmability sits in the driver, not in the dimmer. If a spot does not list a dimmable driver, putting a dimmer in front of it will not make it dimmable. You will get either no response at all, or a spot that drops out at half brightness.

Also watch the difference between a separate driver and a loop-through driver. The Lesto 5W in black has a loop-through driver: you chain the spots one after another. The silver and chrome versions come with a separate driver per spot in the box. That makes no difference to the dimmer, but it does change how much room you need above the ceiling.

Spots with their own settings

Some spots handle part of this themselves. The Lesto has a wattage switch for choosing between 4 and 6 watts, and a CCT switch for 2700K, 3000K or 4000K. That is not dimming — it is a fixed setting you choose during installation. If you want to turn the light right down in the evening, you still need a dimmer.

Not sure which spot suits your ceiling? Our dimmer guide has the full step-by-step, and the recessed spotlights collection shows per spot whether a dimmable driver is included.