How to Wire LED Christmas Lights to a Dimmer

While making the switch from classic incandescent Christmas lights to modern LED (light emitting diode) Christmas light strings is efficient, once you have your LEDs installed, running them at their brightest output all the time is still somewhat excessive.

Wiring your LED Christmas lights into a dimmer will help lower your electrical usage, give you control over how bright you want the lights to appear at any given time, and extend the lifespan of your Christmas lights.

Though the addition of a dimmer may make sense for you, how to wire the dimmer into the lights may not be as obvious. Follow this simple procedure to get the job done right the first time.

Step 1 - Choose LED Christmas Lights

The first step is to choose a set of LED Christmas lights that will do everything you want. Spend time shopping around because the prices of these Christmas lights can vary significantly.

If you've just gotten a shock from the electric bill following your most recent Christmas, you may be able to take advantage of some after-Christmas sales on the lights if you act fast.

Be aware that not all LEDs are ideal or compatible for being wired with dimmers. Be sure to check the product specifications and any information from the manufacturer.

Step 2 - Understand the Concept

LED Christmas lights use a transformer to step the voltage of the AC current down into something that can be used to light the lights up. In rare instances, the power demands for LED lights are so miniscule that even the transformer is too overpowered to meter out the proper doses. In these cases, you must rely on a device called an LED Driver.

A dimmer switch works much like the power transformer in that it limits the amount of current going to the lights, but the dimmer has the added factor of allowing you to control just how much power the lights get.

Step 3 - Choose a Dimmer

Now you need to choose a dimmer that is suitable for use with your Christmas lights. Choose a dimmer that works with DC (Direct Current) electricity because this is what your LED lights will work on. The Christmas lights dimmer should be capable of dimming to the correct voltages to change the brightness of the lights.

Step 4 - Wire the Dimmer

The dimmer simply needs to be wired so that it is in-line with the LED Christmas lights.

Note—Always unplug the Christmas lights before cutting and wiring the dimmer. Although these will use a stepped down DC current that isn't lethal, electrical shocks at any current are best avoided.

Cut the wires where you want to locate the dimmer. Be sure to consider this spot carefully before making the final cut because once you've made the cut you can't change it. Open up the dimmer casing and then screw the wires from the lights into the dimmer terminals. Make sure that the cable clamps are done up tightly on the insulated section of the cable.

Note—Even if you're wiring the dimmer for external lights, it's always better to keep the dimmer switch inside the house. This way you won't have to worry about weatherproofing the connections.

Step 5 - Test the Dimmer

Once you have wired the dimmer into the circuit you then need to test it. Turn the lights on and use the dimmer to change how bright the lights are.

If the lights aren't coming on at all, then it's likely that you haven't made one of the connections properly. If the lights don't change brightness when the dimmer is adjusted, it could be that the dimmer has not been wired properly or that it is defective.

The dimmer can normally act as the switch for the light too, assuming that the dimmer can become infinitely resistant. This way you will be able to quickly and easily control the brightness of the lights.

Step 6 - Enhancements

It's also possible to do various enhancements to make the most out of your light dimmer. For instance, an audio dimmer can be fitted to allow the lights to flash along to music.