Advantage of Trailing Edge LED Dimmers

To change the ambience of a room in your home, an easy way is to dim your lights. But since the rise of LED technology altering the brightness level has become a little bit more complicated. To control the brightness of most LED lights you need to have a so called trailing edge dimmer. Otherwise your lights won’t dim or could fail. In this guide we will cover the advantages of trailing edge dimmers.

What are dimmers?

Dimmers are switches connected to a light fixture. The function of a dimmer is to lower the light’s brightness. This is done by changing the waveform of the voltage supplied to the lamp. This then results in the lowering of the intensity of the light output. If you want to dim your LED bulbs in your home, it is important to ensure that the bulbs and the dimmer switches are compatible.

There are many types of dimmers and they are not all the same. Mainly there are two types of dimmers – the leading edge dimmer and the trailing edge dimmer. These two types of dimmers are also known as phase cutting dimmers. They get their names from the part of the AC waves that they cut off to reduce the power sent to the light source.

Leading Edge

Leading edge dimmers cut off the beginning of the AC waveform.

Trailing Edge

Trailing edge dimmers cut off the end of the AC waveform.

Additionally dimmer switches work within a certain operational load range. If your dimmer switch has a range of 0 to 400W, it is possible to have 10 lamps each having 40W on it, or you can have 8 lamps each having 50W. You can have any combination as long as it adds up to a maximum of 400W.

LED Lights and Dimmers

Because of its energy efficiency and long lifespan, LED lights are often the smartest choice for your home. If you want to create mood lighting and get the most of your LED lights you should use a phase cutting dimmer. This is the most popular among dimming control devices.

There are two kinds of LED lights you can purchase in the market, the dimmable and non-dimmable lights. If you want to dim your LED light source, then you need to have a dimmable LED. You can easily identify one because it will be clearly stated on the box.

LED retrofit bulbs have a built-in driver in their base. This converts AC power to DC power and it helps maintain a constant current to the LED. The problem is that if the dimming system sends a lesser input voltage, the driver will attempt to compensate for the lack. This makes the build-in driver at odds with the phase cutting dimmer. The same goes for LED drivers that are included in LED fixtures such as downlights.

So, if you want your LED lights to work with a phase cutting dimmer, you must have an electronic driver that is compatible with it. You need to replace your LED driver with a dimmable LED driver. This then would make your non-dimmable LED into a dimmable one. However, make sure not to use a dimmer switch on a non-dimmable LED. It may reduce brightness level but the lamp would flicker and soon die out.

Trailing-Edge Dimmers

Trailing edge dimmers are dimmers used typically with electronic drivers. With this type of dimmer, voltage and current are not rushed to the light source. Compared to leading-edge dimmers, trailing edge dimmers have a low minimum load. It then becomes a better choice for dimming low-powered lighting circuits. This is why they work best with LEDs.

When using trailing edge dimmers with LED, it is very important to remember the 10% rule. So, if you have a 400W trailing-edge dimmer, it can easily power 400W incandescent lamps. But with LEDs, the maximum load is only 10%, which means that the maximum load would only be 40W worth of LEDs.

Advantages of Trailing Edge Dimmers

The popularity of trailing edge dimmers today has surpassed that of leading edge dimmers. The reason is because of its advantages over leading edge dimmers like smoother dimming control, soft start, silent running, or the absence of any buzzing noise when in operation, less interference and is ideal for use in most premises.

Although both leading edge and trailing edge dimmers can work with dimmable LEDs, the preferred one is the trailing edge because they work best with dimmable LED drivers. And this is also the reason why most LED manufacturers are designing their retrofit lamps to work best with this type of dimmer.

Low minimum load

The minimum load of a trailing edge dimmer is much lower than the leading edge dimmer. This makes it more suitable for powering LEDs. You don’t need to worry anymore about meeting a leading-edge dimmer’s high minimum load. You just need to use the number of LEDs required for your lighting needs.

Wide compatibility

Trailing edge dimmers are also suitable for all types of lighting, unlike leading edge dimmers. It is also beneficial because it can recognize the load and when switched on, it self-adjusts. The parameters for minimum load are also adjustable.

Because the trailing-edge dimmer has universal usability, then this means that it is no longer required to check whether the switch for your bulbs is correct. The soft-start technology in trailing-edge dimmer switches gives you the most usage of your LED bulbs, since there is less wear put on the LED chips which makes your LED light last longer.

Many features

The features of this LED-friendly trailing edge dimmer which includes soft start, multi-channel, silent-running, and smooth control dimming capabilities shows how the dimmer gives a gentle treatment to your LED bulb. This ensure that you LED will achieve their long-expected lifespan.

The dimming capabilities of trailing edge dimmers that are compatible with your LED driver gives impressive results. The brilliant colors and glow of your LED lights are retained when dimmed. They are also cooler and live longer. The dimming capability range of trailing edge dimmer is 100% compared to only 40% for leading-edge dimmers. This means that you can dim your LED light until it is completely off.


Trailing edge dimmers are the successor of leading edge dimmers. Their main differences are that they cut off the end of the AC waveform and work with a low minimum load. This is why trailing edge dimmers are the preferred way to dim your LED lights without damaging your light bulbs. This way you can create different moods in your home even better as with the old lighting technologies.