Everything you need to know About Triac Dimming for LEDs

led dimmer

You can’t go anywhere in the world today without coming across an LED light fixture. LEDs are great at saving energy. However, LEDs are not yet on par with traditional incandescent light bulbs in terms of color depiction and dimming.

Dimmers with thyristor integrated circuits (TRIACs) are replacing compact fluorescent light bulbs. LEDs, and halogen lamps in residential settings where incandescent light bulbs are still used. Triac is commonly used in these types of systems.

For LED lighting to be viable, it must be both energy efficient and last a long time. It can control high-power devices even though it is made of cheap parts. So, we can say that TRIAC is a good choice for lighting and other large-scale electrical equipment that we require to work reliably.

What Exactly is A Triac?

A TRIAC is an electronic component with three terminals that can conduct current in either direction when it is turned on. This configuration is equivalent to two SCRs with their gates wired in reverse parallel and connected to each other. 

A TRIAC is activated by a gate signal that is analogous to that of a silicon carbide (SCR). Due to the gate signal, the gadget can accept current in either direction. TRIACs were developed to facilitate the management of AC power.

You can choose from a wide variety of TRIAC packaging options. TRIACs are completely safe to be subjected to a broad variety of voltages and currents without fear of harming them. Most TRIACs have a current rating of less than 50 A, far lower than that of silicon controlled rectifiers. Therefore, they are inapplicable wherever high currents might cause damage. 

TRIACs’ are versatile as a device that can operate with either a positive or negative voltage across its terminals that makes them a handy tool. This provides a great deal of flexibility for future redesigns. Since SCRs allow current to flow in both directions, they are not as effective as TRIACs at managing low power in AC circuits. It’s easier to use the TRIACs.

How Does The Triac Dimming Work? 

From AC phase 0, physical dimming occurs when the input voltage is dropped until the TRIAC dimmer is turned on. This continues until the output voltage reaches the desired level. Changing the effective value of the AC is how this dimming system gets its job done. Altering the angle of conduction for each AC half-wave is the first thing that needs to be done.

TRIAC dimming controllers perform in the same manner as quick switches. These are what are utilized to regulate the amount of current that is passing through an LED lamp. When a device is powered on, it will begin to move electrons through its internal components.

Typically, it accomplishes this by severing the voltage waveform and stopping the flow of electricity. When the load reaches its maximum capacity.

Adjusting the intensity of the lights is one of the many functions that a TRIAC controller for LED lighting can perform. Because the switch takes longer to react, there will be less power flow, and as a result, the bulb’s brightness will be reduced.

The total amount of energy that has been freed can be estimated by how fast the switch responds. A large amount of energy is lost whenever a switch has a rapid response time.

Because of its poor response time, it restricts the amount of energy that may be used. As a consequence of this, the LED light will lose some of its brightness. Due to the fact that TRIAC dimming reduces the likelihood of half-wave on failure and Hz flicker.

It does not affect the life of LED bulbs to the same extent as Thyristor dimmers, which are the type that are used.

Through the application of voltages that are diametrically opposed to one another on the TRIAC’s gate electrode.

Controlling the flow of electricity is something that can be accomplished. Power can flow through the TRIAC once it has been activated, but only up until the point when the current falls below the safe level.

The circuit is capable of handling high voltage. Yet the control currents that are required are low. It alters the amount of current that travels through a circuit load. It can be accomplished with the use of a TRIAC circuit and a phase control.

When using an LED bulb with a TRIAC dimmer and seeking for a TRIAC dimming LED driver  you will need to do the following. It is important to make sure that the TRIAC dimming device in question is, in fact, a TRIAC semiconductor device.

There is more than one TRIAC dimmer that can be constructed for resistive loads. When an LED light source is combined with a TRIAC dimmer in an inappropriate manner. There is a possibility that the light bulb does not function properly, as evidenced by humming or flickering. It is possible that the lifespan of LED lights will be reduced if these issues are not resolved.

What is a TRIAC? How TRIACs Work? ( Triode for Alternating Current - TRIAC Tutorial)

Why Choose TRIAC? 

TRIACs can switch high voltages. The TRIAC is a helpful component that may be found in a wide variety of electrical control systems. According to these findings, the concept that a TRIAC can be used to switch lights. It can be used in the same way that we do on a daily basis is supported by evidence.

TRIAC circuits can be used in a variety of ways to control and switch AC electricity. For instance, you can use them to power small motors and fans. Users can do a lot with TRIAC because it is a simple protocol and a control that can do more than one thing.

What is Dimming? 

To change the amount of light and the mood, all you have to do is flip the switch on the dimmer. There are now many kinds of available dimming drivers.

Dimming drivers can be divided into several categories. These are Triac dimmers, LED dimmers with a voltage range of 0–10 V, and pulse width modulation (PWM) dimmers.

Each of these methods changes the output of current, voltage, and frequency. Each method in different ways to change the amount of light coming from the source.

Triac Dimming 

Dimming with a triac was first made for incandescent and compact fluorescent bulbs. But now it is used a lot with LEDs as well. Because triac dimming is a physical process.

Triac dimming starts with AC phase 0 and goes on until the Triac driver is triggered at which point the input voltage drops by a lot. The voltage input waveform is cut at the conduction angle. This makes a voltage waveform that is perpendicular to the voltage input waveform.

Use the tangential direction principle to reduce the amount of power needed to run the common load. This brings the effective value of the output voltage (resistive load) down to a lower level.

The Triac dimmer is the standard in the industry because it has a lot of great features. Features such as precise change, high efficiency, small size, light weight, and easy operation from a long distance.

As a result, it has become the default choice for manufacturers. Dimming with a triac has many benefits. Benefits such as a low initial investment, reliable operation, and low ongoing cost.

PWM Dimming 

PWM stands for “pulse-width modulation”. It is a way to control analog circuits that uses the digital output of a microprocessor. This method is very effective.

This method is used in many fields. It is used in measuring, communications, power control and conversion, and LED lighting, to name a few. By switching analog equipment to digital control, the cost of the system and the amount of energy it uses can be cut by a large amount.

Digital control is also easier to use. That is because most modern microcontrollers and DSPs have PWM controllers built right into the chip. This makes digital control more convenient in general.

Taking a pulse-width modulation (PWM) reading is a straightforward method of logging the intensity of an analog signal. When attempting to determine the intensity of an analog signal. Using high-resolution counters, one can manipulate the square wave’s duty cycle.

In spite of the fact that the full-scale DC supply may or may not be present at any one time, the PWM signal remains digital. A voltage or current source that cycles on and off at regular intervals is provided to the analog load.

The load is connected to the DC power supply whenever the latter is operational. Once you turn it off, communication stops.

With proper frequency bandwidth, any arbitrary analog value can be encoded using pulse width modulation (PWM). For your perusal, a schematic depicting three distinct PWM signals is provided below.

PWM (Pulse Width Modulation) as Fast As Possible

LED 0/1-10v Dimming 

A 0-10v dimming system is an analog dimming method because the driver has two extra ports for +10v and -10v. A traditional Triac dimmer only has one port for +10v and -10v.

The effect of dimming can be achieved by controlling the current that the driver sends out. That is what makes it possible. In this case, 0V is pitch black and 10V is quite bright. On the resistance dimmer, the output current is 10% when the voltage is at 1V, and it is 100% when the voltage is at 10V.

In contrast to 0–10V, which has an on/off switch built in, 1–10V does not, so the light cannot be turned off completely.

0-10V dimming Explained - What is 0-10 volt dimming?  How does it work?  Installation of 0-10v

Dali Dimming 

To wire DALI dimming, you need a control cable with two cores. After the initial installation is done,the lighting management systems make it possible to digitally rewire the lighting circuits.

while staying within the parameters that have already been set. With DALI lighting, LED downlights, LED accent lights, and LED linear systems will all have the best possible control over their light sources.

Even better, no other form of modern dimming technology can match the range of dimming that can be done by these systems. Because of these changes, more recent versions of DALI can be used to control both RGBW and Tunable White lighting.

Dimming ballasts that use the DALI standard can easily handle even the most complicated color-changing applications.

What can DALI do? Lighting quality and control meets intelligence and connectivity.

TRIAC Controller & Receiver

TRIAC controllers let you change many aspects of the lighting. They achieve the effect of a dimmer setting by quickly reversing the flow of electricity, which is how they work.

It applies to LEDs and other forms of lighting technology in the same way.

TRIACs are usually used in high-power situations, such as when lighting, heating, or controlling motors. TRIACs are used to turn electricity on and off more quickly than regular power switches. It helps cut down on noise and EMI that would otherwise be present.

You are able to modify the quantity of power that is sent to a load by making use of a TRIAC receiver. In order to accomplish this, it maintains a tight watch on the voltage that is present between the terminals of the TRIAC and activates the load. 

It is done when that voltage reaches the threshold that has been set.

This receiver can be used in a variety of different ways. Some examples of these are adapters for power outlets, throttles for motors, and dimmers for lights.

The TRIAC receiver is used in a broad variety of industrial equipment, including plasma cutters and welding equipment, amongst others.

TRIAC Dimmers Used in LEDs 

Light-emitting diodes, also known as LEDs, are gaining popularity as a lighting option due to their low energy consumption, long lifespans, and high levels of efficiency.

One of the few disadvantages of LEDs is it can be difficult to adjust the level of brightness. The intensity of LED lighting can be adjusted with a TRIAC dimmer.

TRIAC dimmers change the load current to make changes to the lighting. They do this by quickly switching between active and inactive states. This brings the average current down to a level where it can be safely handled. Due to this, they are an excellent option for usage in situations requiring LED dimmers. Since they are not affected by quick changes in current.

When working with LEDs, TRIAC dimmers provide a few one-of-a-kind problems that need to be addressed.

Before you install an LED, you should first check to see if the dimmer can be used well with it. Checking the current rating of the dimmer is the second step in making certain that the dimmer is capable of managing the amount of power that the LED will consume. Third, you need to make sure that the dimmer and the LED are linked properly by wiring them together.

TRIAC dimmers are an excellent tool for reducing the amount of light that your LED lights produce if you follow the instructions provided above. The brightness can be easily changed, and there is no flickering or other annoying effect.

In addition to everything, they are compatible for use with a diverse selection of LED light fittings and bulbs.

What is Leading Edge? 

Traditionally, incandescent and halogen light bulbs have been used with these dimmers. Since these dimmers were made to work with incandescent light bulbs, they need a lot of power to work. Because of this, their value is limited when combined with low-energy lights like LEDs.


Due to the fact that LED lights use so little power, they might not meet the minimum load requirements of cutting-edge dimmers.

Because of the demanding minimum load requirements of a leading-edge dimmer. You won’t be able to get the effect you want by using just one of these dimmers with a single LED light string.

LEDs use less energy than other types of lighting, so they can give off more light while using a lot less power. With today’s high-tech dimmers, it would be possible to make more light than is actually needed.

To dim lights with lower wattages, such as LEDs, you should make use of a trailing edge dimmer rather than an earlier style of dimmer switch. This is the case since trailing edge dimmers are more efficient. This happens because trailing edge dimmers are more sensitive to small changes in voltage.

What is Trailing Edge? 

The newer leading-edge dimmers are better in a number of ways than the older leading-edge versions.

The fade-out is now much more quiet and slow, and there is much less buzzing and interference because of these changes.

Minimum loads for trailing-edge dimmers are much lower than those for leading-edge dimmers.This makes them better for powering LEDs.


When dimming LED lights with a trailing edge dimmer, the 10% rule needs to be followed. It’s true that a trailing edge dimmer with 400W of capacity can easily handle 400W of incandescent bulbs, but the most LEDs can handle is just 10W. That is to say, our 400W dimmer can only control a maximum of 40W of LED lights.

Low-wattage loads are most effectively managed by trailing-edge dimmers. Since you don’t have to worry about the large minimum load that leading-edge dimmers require, you can use as many LEDs as you want to get the effect you want.

Differences Between Leading-edge and Trailing-edge Dimmers 

Leading-edge dimmer switches were used to dim incandescent, halogen, or wire-wound magnetic transformers.

This was done because leading-edge dimmer switches were easier to install. It also costs less to buy than trailing-edge dimmer switches.

Because of a TRIAC switch, also known as a “Triode for Alternating Current” switch, which is utilized to regulate the quantity of electricity that is utilized. Which is another name for these devices is “TRIAC dimmers.”

Because they have a high minimum load. The leading-edge dimmer switches that are currently used are not compatible with lighting circuits that use low-power LEDs or CFLs. But the type of dimming control that is the most popular right now is the most recent one.

The functionality of trailing-edge dimmers is more complex than that of their leading-edge counterparts. Because they are quieter and smoother, they can be used in most types of buildings.

Because it has a lower minimum load, a trailing-edge dimmer is better than a leading-edge dimmer. For dimming lighting circuits with smaller, less powerful bulbs.

Lamp Dimmers - Leading and Trailing Edge

What is A Dimming Curve? 

The dimming curve is the name given to a parameter that the dimming device would usually list as it worked. After processing the input signal, a dimming device will usually make the light output match a function that has been set up ahead of time.

This will happen after the device has handled the signal. As an example of the function, the fading curve can be seen in this figure.

When looking to buy dimming equipment, this is one of the most important things to think about. It has an immediate effect on the effect that the light output has. It is also the physical representation of how the digital dimming equipment works.

Types Of Dimming Curve 

Based on how they look, dimming curves can be separated into a number of different types. We’ll talk about the linear dimming curve and the logarithmic dimming curve. Both are main types of dimming curves (sometimes called “square-law” dimming).

When using linear dimming curves, the amount of light that comes out is directly related to the amount of energy that goes into the system. The strength of the input signal, which in this case is 25%, will be exactly the same as the output value.

So, when logarithmic dimming curves are used, the values of the inputs change as the dimming levels go up. When the brightness is lowered, the signal sent to the driver will change more slowly. But when the brightness is raised, it will change more quickly.

A dimmer, which is an input device, or a driver, can have any curve programmed into it, such as a “S” curve, a “soft linear” curve, etc (an output device). This type of input range, which is also called a “slider,” is usually meant to give you more precise control over a portion of the total input range.

If, on the other hand, you tell the makers of architectural products that you want “linear” or “logarithmic” for all the input and output devices, then you can expect the best possible results.

TRIAC LED Control System And Its Wiring 

Simply adding a TRIAC into the circuit will allow the brightness of an LED to be adjusted to the desired level. The TRIAC is a semiconductor device with three terminals. To turn it on, a voltage must be applied to its gate terminal. It can be turned off when the voltage is removed from that terminal.

Because of this, it is a great choice for the task in question. Which involves precise management of the current that is flowing via an LED.

Before you can begin installing a TRIAC dimmer in your house, you will first need to remove the standard light switch that is currently there.

It is necessary to make a connection between the black wire that is coming out of the wall and the black wire that is coming out of the dimmer. Following this step, you will need to connect the white wire of the dimmer to the white wire that is already present in the wall.

At last, you are able to make the connection between the green ground wire on the dimmer and the bare copper ground wire that is located in the wall.

Advantages And Disadvantages Of TRIAC Dimmers In LEDs 

TRIAC dimming has many benefits. benefits, such as a high degree of efficiency. It also gives a high level of adjustment precision. It provides a light-weight construction. It also has a tiny and compact size and an easy-to-use remote control, which are some of the benefits of this product.

The TRIAC dimming method is the most common type of dimmer you can buy right now. There is a wide range of products that are made using this method.

One of the many advantages of utilizing these dimmers is the fact that they have a low dimming cost when utilized in conjunction with LED lighting. This is one of the advantages of using these dimmers.

Because of how poorly it dims, a TRIAC dimmer has a limited dimming range. This limits the dimmer’s overall range of motion. Using this kind of dimmer has this drawback.

There is still a very slight amount of current going through the TRIAC switch even when it is turned down to its minimum setting. This is because the TRIAC switch’s function is to start electrical flow. With the way LEDs are dimmed right now, this is a tough problem that needs to be solved.

LED Strip Sample Book


The TRIAC dimmable LED driver checks the input phase or RMS voltage when turned on. This determines the dimming current. Most TRIAC-dimmable LED drivers have “bleeding” circuits. Bleeding circuits keep the TRIAC active. This usually requires replacing the bleeding circuit. Adding power and control circuitry changes it.

TRIAC transformers are sometimes referred to as phase dimmers or phase-cut dimming transformers.

First, connect the L/N terminals of the LED drivers to the OUTPUT on the dimmer.

In the second step, connect the positive (LED+) and negative (LED-) ends of the LED driver to the input port of the light.

In the final step, connect the input of the dimmer to a power source.

Forward phase-cut dimming. You may also hear this referred to as “incandescent dimming” or “Triac dimming.”. It is the most common type of dimming.

Dimming with a triac uses leading edge dimming.

Electronic low voltage is the power produced by electronic devices. An ELV dimmer has many other names. Electronic dimmer switches are known by several names. These include low voltage electronic dimmers and trailing edge dimmers. This dimmer gradually brightens and dims your LED.

MLV dimmers are also called magnetic low voltage (MLV) transformers. These are used to control magnetic low voltage transformers in low voltage lighting fixtures. These transformers are used in low-voltage lighting fixtures.

ELV dimmers and transformers are usually more expensive than MLV transformers. but they work more quietly, give better control, and usually last longer (MLV)

Yes! TRIAC mains is (~230v) dimming

0-10v dimming refers to a standard analog dimmer control. This method is also known as dimming through a 0–10V signal. It is different from the Triac dimming method in that it adds two ports on the driver for +10v and -10v. By changing the voltage from 1 to 10v, it is possible to control the amount of current that the driver sends and create a dimming effect.

Yes! Lutron’s dimmers are TRIACs.

0-10V dimming PWM dimming (pulse width modulation dimming), Forward-Phase dimming (also called “Triac” dimming or “incandescent dimming”), and Reverse-Phase dimming are the most common ways to dim LED lights (sometimes referred to as an ELV or Electronic Low Voltage Dimming)

No, you can’t lessen the brightness of an LED by giving it a lower voltage.

No, TRIAC dimmer doesn’t need a neutral

Lutron is the most well-known brand in the industry as well as one of the most well-regarded brands. Still, there are newcomers to the industry who are creating their own names for themselves. They are pursuing novel techniques to dim TRIAC lights using smart technology.

The TRIAC trigger circuit lets the dimmer charge up before turning it back on. These seemingly random restarts of several TRIACs cause noise and LEDs to flicker.

Yes! Both systems are compatible with TRIAC.

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