For any job, LED strip lights are a great way to add light. However, there are times when you'll want to be able to change how bright an LED strip is.
You might want to use them at full brightness while reading a book and then turn them down later to set the mood.
If you're not sure how to do it, keep reading to learn about different ways to dim an LED strip!
First, to clarify: Virtually ALL LED strips are dimmable
When you buy popular LED lights for your home, like A-style bulbs, the product description may often say "NOT DIMMABLE." One reason some LED lights can't be dimmed is that the electrical circuitry inside the LED bulb wasn't made to understand the fading signal from a wall dimmer; that circuitry was made for a regular incandescent bulb.
However, LED strips are not meant to be hooked directly to line voltage, like a 120V AC wall plug. They need a power source to change the higher voltage AC into a lower 12V or 24V DC voltage.
This means that if there is a wall dimmer, it needs to "talk" to the power supply first, then it can dim the LED strip. So, whether something is dimmable or not depends on the power supply unit and whether it can understand the dimming signal sent by the wall-dimmer.
On the other hand, almost all LED strips (not just the strips) can be dimmed. Any LED strip's brightness can be changed as long as it has the right DC electrical signal, which is usually PWM.
What steps should be taken to make sure the LED strip gets the right DC signal to dim? There are two main choices, which we will talk about below.
This is probably your best bet if you like the style and ease of use of standard wall dimmers and want to put an elegant LED strip that will stay in place (for example, under cabinet lighting).
Since most wall dimmers on the market today use the TRIAC dimming signal, you will first need to find a power source that can work with TRIAC dimmers.
The TRIAC adjustable power supply does two things here:
1) lower and flip the 120V AC signal so that it's a 12/24V DC signal that the LED strip can use; and
2) Figure out what the wall dimmer's TRIAC fading signals mean and then turn them into the right LED strip light output.
You can connect the TRIAC adjustable power supply straight to the TRIAC wall dimmer. The power supply's output end is then connected to the LED strip. Because we are working with wire that runs inside the walls, these parts probably won't have any of the plugs or ports you are used to seeing. The power source will also probably be hidden in the wall or an electrical box.
The power supply unit should also be placed as close to the LED strip as possible to reduce the effect of voltage drop.
Just remember that any solution that includes a wall switch, including this one, needs to be hard-wired into the power supply and should only be done by trained and licensed professionals. When working with electricity, you should always be careful!
Are you afraid that you will mess up the wires in your walls? It's okay, you can use parts that only need power from a normal wall outlet as an alternative.
Between a regular power source that doesn't have TRIAC dimming and the LED strip, a DC PWM LED strip dimmer can be put in place. It normally has a slider (turn dial) that lets you change how bright the LED strip is.
It doesn't have to be TRIAC adjustable, and the power source can be any old DC power supply. Compared to TRIAC adjustable power supplies, these power supplies are usually less expensive and easier to find.
This is a very basic circuit that will work well for smaller or movable setups where the dimmer doesn't need to be built into the wall. Unlike TRIAC dimmable power supplies, these standard power supplies usually come with standard 2-prong plugs that can be plugged into any wall outlet.
From the power source, connect the two output wires to the dimmer unit. Then, connect the two input wires from the LED strip. The dimmer is just like a valve, and the power source unit will give the right amount of current and voltage based on where the knob is on the dimmer.
This is helpful if you plan to move the LED strip installation around a lot, but it might be a problem if you want something more fixed or less "cluttered."
The PWM switch has to be put pretty close to the LED strip, which is another big problem with this method. This is because of something called voltage drop, which only happens in low voltage DC uses. You could avoid this with Option 1, which is a wall switch.
Last things to think about
It can be hard to install and dim LED strips because we are currently living in a time when both new DC technology and older TRIAC dimmer systems are still popular in both new and old homes.
Because the parts and combinations can be different, we highly advise trying for compatibility before making any fixed or large-scale builds. Problems like fading or non-linear dimming can happen out of the blue, and it's best to catch them as soon as possible.
