Do you love setting the atmosphere with your light? Or do you want to save more energy? It’s possible with your dimmable LEDs, depending on how you tweak the configuration. However, dimming LED lights can get tricky. For example, some “dimmable” LEDs may not work with specific dimmers. And using a dimmer with a non-dimmable LED would reduce your lamp’s lifespan. This article will give you tips and tricks on dimming LED lights without issues. We’ll also add some factors to consider when choosing a dimming method.
Why Dim your Lights?
Dimmer Switch
It’s beneficial to dim your lights. First, dimming can extend your lamp’s lifespan. How? Well, dimmed lights generate less heat, which means less stress for the lamp’s components.
Additionally, you can enjoy extra energy savings. For example, dimming your lights at 50% means your lamps would use 50% less energy.
Furthermore, dimmable LEDs have ambiance effects that can help you set the mood of your environment. In short, it’s pretty flexible and can work for any situation.
How do Dimmable Lights Work?
You can dim your lights in two ways: Analog or pulse width modulation. The analog method is pretty simple. You’ll need to increase or decrease your lamp’s current to brighten or dim the lights.
The PWM method, on the other hand, is a bit more complex. Here, you’ll create a dimming effect instead of voltage to determine your lamp’s brightness level. Also, the “on and off” cycle is responsible for the dimming development.
For instance, if you dim your lights to 20%, they will stay on for 20% of the time and go off for 80% (We’ll discuss more details later).
How Exactly are LEDs Dimmed?
Rotary Dimmer Switch
LED dimming is a different ball game compared to other legacy lighting types. Hence, it’s crucial to plan carefully for dimming when setting up an LED fixture.
For instance, when the filament wire of incandescent bulbs gets hot, it produces light. So you’ll only need to supply less voltage to cool the wire and dim the light. It’s an example of analog dimming since adjusting the voltage can control lights from 0% to 100% brightness.
In contrast, LEDs generate light from diodes. And diodes have only two states: ON (producing lights) or OFF (no light). For this reason, dimming LEDs are a bit different, and here’s why:
Pulse Width Modulation (PWM)
PWM dimming is a perfect match for LEDs as it varies how long the lights stay ON or OFF at any given time. But as we mentioned earlier, the lights will go through ON and OFF cycles to constantly output the desired brightness. But why don’t we see it?
LEDs with PWM dimming can flicker at high rates–which is invisible to the human eye. Typically, we only see about 60 frames per second (50-90 Hz). So, when the lights flash at higher rates, our brains make it look smooth by filling the vision gaps.
But there are certain limitations, especially if you’re using this method in videography. Though we can’t see the PWM flickering, a high-quality camera will pick up little strobes when you dim the lights.
Analog Dimming
While it sounds like an easier option, analog dimming goes beyond adjusting the voltage flowing to the LED. Although it’ll reduce the LED’s brightness, it may change the light’s color at lower voltage levels. As a result, you’ll have light quality and uniformity problems.
No doubt, analog is much easier than PWM dimming for LEDs. After all, it requires adding one or more resistors to your LED connection. But you won’t have as much control over the power supply as PWM dimming.
Additionally, adding resistors depends on your LED’s brightness in its original state. Hence, you’ll need to do some calculations.
First, you must know the power you need for your project. Here’s the formula you need for this calculation:
According to the formula, P (power) is equal to a square of I (current in amps flowing through the circuit) multiplied by R (resistor value in ohms).
How to Dim LED Lights
Dimmer Button
Here are six steps to help you dim your LED lights:
Step One: Check if You have a Dimmable LED
Dimmable LED Bulb
Before getting a new LED dimmer switch, check if your LED fixture is dimmable. And it’s because not all LEDs have dimmable designs. You can find this information behind your light’s packaging or the manufacturer’s website.
Step Two: Check your Existing Dimmer
Light Dimmer
In most cases, you’ll need a special dimmer compatible with your LEDs and lighting choices. You can try to see if it works, but there’s a high chance it won’t. If you have an existing dimmer switch, it may not have designs that support LED lighting loads.
Step Three: Choose your LED Dimmer Switch
There are generally two types of LED dimmer switches:
- Leading edge
- Trailing edge
Most manufacturers use trailing edge dimming, but you know that by looking at the specifications closely.
Note: These types can come as separate switches or a switch with both options.
Step Four: Select your Lighting Load
Usually, LED dimmer switches to have maximum capacities that work with the connected LED lights. However, you’ll need extra care selecting your LED lighting load to avoid damage.
If a dimmer switch has a 400W maximum capacity, you can use light loads up to that point. Also, you can use higher loads for better performance, but you shouldn’t go lower.
Step Five: De-Rate Your LED Lighting Load
High-quality dimming can be tricky because dimmer switches behave differently with various LEDs. But, you can reduce your LED lighting load by 90% to stay safe. Don’t do this if the manufacturer’s instructions state otherwise.
You can calculate the number of LED light bulbs your dimmer switch can support by dividing the load (minimum and maximum) by 10.
For instance, if you have a dimmer switch that works from 0W to 400W, the calculation will look like this:
- Minimum load: 0W/10 = 0W
- Maximum load: 400W/10 = 40W
So based on the calculation, you can only use one LED with a maximum of 30W.
Step Six: Select the Correct LED Driver
Drivers are responsible for supplying power to your LEDs. Hence, you may have issues if it’s incompatible with your dimmer switch.
Like an LED dimmer switch, every driver has different specs and will only work with specific LEDs. So, you must check all specifications carefully to avoid compatibility issues.
How to Dim LED Lights: Other Types of Dimming
Traditional Dimmer Switch
How to Dim LED Lights: Phase Control
Phase control is a common dimming type for LEDs that reduces the light source’s power supply. As a result, it shortens the power cycle’s duration, dimming the light output.
Phase control has two types: trailing edge and leading edge. For the leading edge, you’ll reduce the power supply to dim the lights at the start of the cycle. In contrast, the trailing edge reduces the power supply at the end of the process.
0-10V
Here, you’ll pass a 0-10V DC via a resistor, which creates a voltage drop that dims the lights. It’s a method that works for fluorescent lights, but you can use it on some low-voltage AC LEDs.
1-10v
1-10v dimming uses one wire to send control signals from a lighting controller to a dimmable driver. Also, the wire’s voltage determines the fixture’s light output.
How to Dim LED Lights: DALI
The primary function of DALI is controlling lights. Also, you can use it to dim LEDs and other lighting sources with different methods. These include trailing edge, 0-100%, and leading-edge.
FAQs
Do LED Lights need Special Dimmers?
Most times, yes. There’s a high chance regular dimmers won’t be compatible, so you’ll need a special dimmer with matching specs for your LEDs.
Are Dimmable LEDs expensive?
Dimmable LEDs can cost a bit more than non-dimmable variants.
Is Dimming Bad for LEDs?
Dimming is not harmful as long as you have dimmable LEDs. However, using dimmers switches on non-dimmable LEDs would shorten their lifespan.
Rounding Up
Man controlling LED
Dimming is a great way to set up the mood and save energy. And there are several ways to do it with LEDs.
However, you must consider your project’s size and preferred dimmer interface before you choose a dimming method. If you’re working with a sizeable task, DALI, DMX, and 0-10v LED dimmers are your go-to. You can use PWM and analog dimming for smaller projects.
As for the dimmer interface, you can choose touchscreens, WiFi functions, or rotaries for your application.
Don’t hesitate to contact us if you have any questions.
