Types of dimmer switches you can get

In this article you`re going to learn about the types of dimmer switches there are available.

There are hundreds of dimmers on the market and I know it can be difficult to choose the right type of dimmer, they almost all look the same and with a bunch of model numbers it can get a bit overwhelming.

 

Basic dimmer information

So let`s go over the basic information and determine the type of dimmer you should get.

Single-pole dimmers are used for lights controlled from a single dim switch in one spot. Example of a Leviton single pole dimmer.

 

Three-way dimmers are used for lights controlled by one dimmer and one or more switches in other places. Here`s a Lutron 3-Way Dimmer.

 

Several or multi-location dimmers are used for lights managed by multiple companion dimmers allowing for full lighting control from four or more locations. Here`s a Lutron Multi-Location Dimmer.

 

Plugin dimmers are used to dim bulbs in table and floor lamps. You just plug it into your lamp and wall socket. It helps you save energy and extends the lifespan of your bulbs. Example of Lutron plug-in dimmer.

 

Types of dimmer switches

Trailing edge and leading edge dimmers

Okay, so there are many types of dimmers available, but the most popular are the two that we’ll be concentrating on  are leading edge and trailing edge phase-cut dimmers.

As their name implies, both work by trimming the voltage at various phases of an alternating current’s sine wave and thereby reducing the power they send to the bulb. Now, at this point I’m aware that there’ll be some amongst you that are itching to know exactly how this works, which is why I’ve kindly included a link to our leading edge and trailing edge dimmer guide.

• Leading edge dimmers are the most popular of the two. They’ve been around for a long time and are traditionally used to dim normal incandescent and halogen bulbs. They have a much higher wattage range usually anywhere between 250W and 1000W and because of that they don`t operate well with low wattage LED bulbs, though this can be  achievable if the required tolerances are met.

• Trailing edge or LED compatible dimmers have been designed for use with LED bulbs and because of that they share a number of characteristics that make them much more compatible, such as comparable wattage ranges and an inherently digital make up. The needed wattages for these dimmers are way lower, making them more compatible with the lower wattage of LED bulbs. But again, trailing edge dimmers can also be used to dim normal bulbs if the wattage tolerances are still met, and they do this more effectively than using a leading edge dimmer to dim LED bulbs.

Universal Dimmers

Universal Dimmers are used to control halogen, incandescent, dimmable CFL and dimmable LED bulbs.

They offer maximum-range dimming, soft start-up, and eliminate flickering of lights. When using CFL or LED bulbs with a dimmer, check that the packaging on the bulb shows that it is dimmable. Most bulb and dimmer manufacturers gives bulb compatibility information on their sites.

Halogen and Incandescent Dimmers

Halogen/Incandescent Dimmers are used to control halogen and incandescent bulbs. You are not supposed to use them to control CFL and LED bulbs or dimmable CFL and LED bulbs. If you use them for that, it may result in bad performance.

Electronic Low Voltage Dimmer (ELV)

ELV Dimmers are used to control electronic low voltage transformers and dimmable LED power supplies ex. ELV track lighting, Led strips and under cabinet lighting . For installation ELV Dimmers needs a neutral wire.

Magnetic Low Voltage Dimmer(MLV)

These Dimmers are good for recessed lights which are often magnetic and low voltage. Magnetic low voltage lights are often heavier and larger than electronic low voltage.

Fluorescent Dimmers

Fluorescent Dimmers are used to control fluorescent lights.

High Wattage Dimmers

These dimming devices are used to control high wattage lighting, mainly 1000 W. If you have a fixture with over 600 W your choice should be a HWD.

An important thing to remember is that, use only one type of bulb in a lighting fixture, otherwise it may cause some trouble in performance.

 

Dimmer switch wattage calculation

Now you`re maybe wondering, but what about wattage?

Dimmers come in many different wattage models. The most typical dimmer wattage ratings are 150 watts, 300 watts, 600 watts and 1000 watts. 150 watt rated dimmers are usually used for a single bulb. You can find the wattage rating usually on a sticker on the light fixture.

Dimmers are built to control many wattage loads and levels. You should select the dimmer by your wattage requirements. The calculation could not be easier.

Here`s how you calculate dimmer wattage.

Do like this:
Add the total wattage of the bulbs you want to dim. Like this, a fixture with three 50 W bulbs has a total wattage of 150 W (3 bulbs x 50 watts).
You can use a 200 W dimmer or bigger in this case.

What about when you have 2 dimmers then?

You calculate it the same way. Say you have six 50 W lights in a room, but they are split, there are 3 lights per dimmer.

First dimmer: 3 x 50 W=150 W

Second dimmer: 3 x 50 W=150 W

You will need two 150 W or bigger dimmers in this case.

Dimmer switch control designs

With a wide array of control options, styles, and colors, you can choose from hundreds of stand-alone dimmers.

 

The most used styles of dimmer switches

With so many styles of dimmers to choose from, you are very likely to find one that fits your needs. So let`s go over the most used models and couple of funny ones too.
Rotary dimmers are classic, you adjust the lighting level with a rotating knob.

Toggle dimmer switch up and down like a normal switch, but the level of light returns automatically to the last level that was set.

Slide dimmers slide up n` down and are available in preset or slide-to-off designs.

Rocker dimmers resemble a decorator-style rocker switch that “rocks” up and down to return the light to your favorite level.

Tap/Digital dimmers feature a touch pad or button controls that return light levels to your preset level. Some tap levels have LED lights that indicate the current light level.

Scene selector dimmers feature multiple buttons that let you switch to different light levels.

Maybe you want something totally different?

Take a look at these:

 

What dimmer switch should i use?

In conclusion:

Determine the number of switches that control the light group. If only one switch controls the light, purchase a single-pole dimmer. If two switches control a single light or a group of lights, you will need a 3-way dimmer.

Then look at the bulb type you are going to be using and pick the right type of dimmer. The universal dimmer model will do it for most locations.

Let`s take a closer look at how a dimmer switch works

By altering the amount of power delivered to a light source, a dimmer directly affects the level of light output from that source.

The more power delivered, the higher the light output. The less power delivered, the lower the light output.

On Off Switch

The two extremes of light output range are of
course achievable by a simple switch.

With a simple switch, we either turn the light on, meaning we close the circuit, delivering full power to achieve the full light output capabilities of the lighting mode or we turn the light off.
Meaning we open the circuit, cutting off power from the lighting load and getting no light output in return.
While this explanation is obvious and simple, the concept is actually foundational to the understanding of how typical dimmers work.

In order to achieve light level from are given lighting load, that is somewhere between fully bright and fully off, what the dimmer actually is doing a switching power on and off at a high rate of switching. Thereby reducing the power delivered to the lighting load and resulting in a lower light output.

High Frequency Switch

The frequency of the switching, is high enough that you cannot see it.
The very nature of the power delivered by the electric company makes this feasible.

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This graphic represents a single cycle that delivered sinusoidal voltage signal. This cycle repeats 60 times every second.
Using a simple light switch and turn that switch on, we will be delivering this voltage to the lighting load throughout the entire cycle.

 

As a result, current would flow through the lighting load.
The product of the voltage applied and the resulting current through the lighting load to determine the power delivered to the lighting load.

To reduce the light level output again, we need to reduce the amount of power that’s delivered. We will do so by switching twice,
off and on during a cycle. Using power electronics, such as a triac, we can turn the voltage off, where the sine wave crosses the zero line. Then we leave it off for certain delay, then back on in order to deliver some power, reduced power to the load.

And we do that again on the negative side. The longer the delay before turning on, the less power we will be delivering and the lower the light level of the light source.

Forward Phase Dimmer

So this then would be the modified waveform coming out of the forward phase dimmer. So this is how a standard dimmer works.

A dimmer with the output characteristics explained here, is known by many names, including standard dimmer, household
dimmer, incandescent dimmer, triac dimmer, magnetic dimmer, forward phase dimmer, leading edge dimmer. I will refer to this throughout the remainder of the article
as a forward phase dimmer.

Keep in mind that these dimmers were developed for dimming conventional light sources. Particularly incandescent lamps.

Resistive light sources

These light sources are resistive in nature and they don’t care about the shape of the wave applyed. They will react to how much power is delivered to them, regardless of the waveform.
When the lamp is low voltage and a transformer is used to convert the line voltage to 12 volts, for example to apply to that lamp, then the addition to the lamp itself, some complexity is introduced by the transformer.

Now conventional wire rounded magnetic transformers are compatible with this type of dimming or forward phase dimming,
so long as certain factors are implemented in the dimmer.

For example:
The power delivered during the positive half of the cycle, must equal the power delivered to the negative cycle. So that any DC component the power delivered is within tolerance of transformers, and out of tolerance, DC component would cause the transformer saturate, leading potentially to its failure.

Incandescent dimmer vs magnetic dimmer

So the difference between an incandescent rated dimmer and a
magnetic rated dimmer, is the ladders ability to perform without detriment to the transformer -they are both forward phase dimmers.

Electronic dimmer switch

At one point the history of light source development, the electronic
transformer was introduced, with a very different set of characteristics from those of a magnetic transformer.

One key difference is that, it is not all compatible with a sudden voltage rise, that occurs twice during each cycle.

So there’s a compatibility issue between the electronic transformer and the standard dimmer – you cannot use the two together.
The solution to dimming electronic transformers is, to swap the sequence of power delivery to the lighting load each half-cycle, instead of opening the switch at the beginning of the cycle,
the switch is closed and at that point the power is delivered for a time.

Then after a predetermined delay, the voltage is turned off and power is no longer delivered for the remainder of the half cycle.

In this way, no sudden voltage rises occur, so it works with the electronic transformer.

Elv or electronic voltage dimmer

Dimmers that produced this backward wave form, are more known by the following terms: elv or electronic low voltage dimmer, simply electronic dimmer, reverse-phase dimmer
or trailing edge dimmer.
I will refer to these from here on out as reverse phase dimmers.
Again the incandecent light source, without a transformer doesn’t care about the waveform. So we can then dim line voltage
incandescents with either forward Phase or reverse-phase dimmers.

However the following differences exist.
The triac that is used to perform forward Phase dimming, cannot be operated in reverse phase matter and so different electronics are used for reversed-phase dimming – typically a FET or an IGBT.

These electronics are comparable more expensive than a triac and their current ratings are typically lower. So if you use reverse phase dimming you will pay a premium and your load capacity will be
somewhat lower, compared to the forward phase dimmer.

Compatible dimmer switches

I should mention here, that some electronic low voltage transformers have been modified, specifically to be compatible with forward phase dimmers.

The manufacturer of the elv transformer must state, that it is compatible with forward phase dimmers or a electronic transformer should always be paired with a reverse-phase dimmer.
As these two introduced dimming methods share a common
concept, of switching power on and off during each half-cycle and because they’re not the only means of dimming, we’re going to classify them together and refer to them collectively as phase counter phase control dimming.

While phase control is still the primary dimming method, it is not the only method. Historically there came a point, when it became desirable to dim fluorescent light sources, but fluorescent lights don’t typically respond well to phase control dimmers.

So other methods of dimming became commercially available.
All of which have carried forward in one form or another to LED dimming.

These other methods of dimming differ from phase control dimmers, in that the dimmer is not actually directly modifying the power delivered to the lighting’s load.

Rather it’s sending a signal, a control signal to an intermediary electronic circuit, known as a dimmable ballast in the fluorescent fixture or is a dimmable driver in an LED fixture.

Indirect dimmer switches

The signal is used to communicate to what level the light output should be set and the ballaster driver uses some mechanism beyond the scope of this article, to achieve that lighting level. For this reason I refer to dimmers that use these methods as indirect dimmers.

Indirect dimmers are of two major types: analog and digital.

I will discus the analog indirect dimmers first.

A light source which includes indirect dimming capability, will be looking for a variable control signal, separate from the power delivered, that power typically being switched on and off by the controlling dimmer, in addition to the variable control signal.

The first type of control signal I will discuss, is the variable low voltage output – sometimes referred to as zero to ten dimming.
Such a device will react to a control signal, that varies between 0 and 10 volts DC, to regulate the light output.
If the control signal received is 10 volts, the device causes
the light output, to go to its full on value.

If the control signal received is zero volts, the device causes the light output to go to its minimum or off value.

A control signal value of 5 volts, being at the midpoint of the
control signal range, would cause the light output, theoretically to go to the fifty percent output level.

The second method of analog indirect dimming is pulse width modulation or PWM.

In pwm a constant voltage square wave, a repeating square wave as a control signal.

Now the percentage of the time that the voltage is on, is actually the variable.

We don’t change the frequency, we don’t change the voltage, we just change the duration, then it is on. And that goes between 0 and 100 percent.

Now there is a standard that applies to dimming pulse width modulated control light sources.

That standard is actually opposite of what you might expect. Meaning that if I were to actually apply zero percent of the time
voltage, then the light output is actually going to be a hundred percent and reduce down linearly to 0 percent when we apply a hundred percent of the time the voltage – opposite of what you expect.
Now because it is opposite of what we expect, you do find from time to time manufacturers of PWM control light sources that don’t comply and go more with what you would expect.

With those light sources, if I apply a zero percent of the time the voltage, then I will get 0 light output.
And I will increase linearly up to a hundred percent or full output when I get hundred percent of the time that I’m applying voltage.
A third and final method of analog indirect dimming, uses a
line voltage phase control waveform as a control signal.
Such a device, is characterized by a neutral conductor, a conductor for power switching and a conductor for dimming control.

So it’s known as a three-wire balusters – a three-wire driver.

While the power delivered to the light sources switch
between the switch leg and neutral, in addition a face control signal is applied between the third conductor neutral, to signal the desired light output level.

Finally there is indirect digital dimming, where in we will send a series of bits, according to a preset protocol to communicate commands and status updates over a two serial communication port.

Two examples of this are DMX and Dali
while these technologies are mentioned to round out the discussion of dimming control, they fall outside of the scope of this article.

I hope you understand a little bit more about dimming now.

Led lights can be dimmed using any methods discussed in this article.

That`s pretty much how a dimmer switch works.

How to Buy a Dimmer Switch?

Light dimmers either by themselves or as part of a bigger dimming system, switches, and controls can be a confusing topic. Leviton and Lutron are popular for their variety of light controlling dimmers and switches. Let`s take a look how to select which dimmer is best suited for your home.

Dimmer Lighting Guide: Why you should use a dimmer switch?

Here are a few reasons why you should buy a dimmer:

• save energy
• make your room multifunctional
• better focus
• set the right mood
• help you relax
• boost your productivity

Good lighting is an important piece of your daily well-being. We often choose the paint, floor, furniture and other interior accessories after long consideration. But we often forget the most important thing, the lighting.

The right amount and type of light helps you focus, set the mood and relax when needed.

The correct light setting really brings life to the room. You can get your rooms multifunctional with a dimmer switch – convert dining room to a studio, workroom, office and even a game room for the kids.

The right amount of light increases your productivity too. With a light dimmer you can adjust the amount and form of light in a given area for specific chore or environment.

Using the correct light, not only improves the experience, it assists to save energy and money by using the right amount of light in every situation.

Save energy by using a dimmer

Any dimmer automatically saves 4-10% in electricity, even at the brightest lighting levels, over a normal light switch. Dim the lights and you save even more.

A regular light switch only saves energy in the switched off position. Dimmers and controls save money 24-7. On average, dimming an incandescent or halogen light will reduce energy use by about 20%.

Dimmers extend the life of a bulb

Dimmers reduce electricity to the light bulb, so you can save energy and extend bulb life up to 20 times – a big money saver right there. Plus you get cooler bulbs when a dimmer is used, that can convert into much cooler rooms and that`s a very nice benefit in the summer.

After installing dimmers, you can really experiment with your new lighting, use it for your advantage and make changes when needed.

What tools do you need to install a dimmer?

You don`t want to hurt yourself while installing, that`s why a voltage tester is always good to have available.

Voltage tester

 

Screwdriver

 

Wire strippers

 

Wire nuts

Wiring a dimmer light switch

How to replace a light switch with a dimmer?

Let`s get started:

Light dimmer switch history goes back to 1896, when Granville Woods patented his Safety Dimmer.

Early dimmers were controlled through the manual manipulation of large dimmer panels. This demanded all power to come through the lighting control spot, which would be inconvenient, amateurish and very dangerous for large powered systems.

Over the last decades, their energy efficiency has improved drastically.

Ever heard the buzzing sound from a dimmer?

The earliest dimmers decreased a light’s brightness by feeding less electricity into the bulb and converting the remaining energy into heat. That`s the reason why older dimmers and lights would get very hot – and bring up your electric bill.

 Ever heard a dimmer buzz? That was one of the side effects when energy was being converted to heat. Yeah you get the nice perfect light you wanted, but you also got the background sound of your electric bill ticking sky high. It got the job done, but this was a risky and inefficient method that didn’t actually save energy.

Now, thanks to engineering advancements and technological improvements, modern dimmers have the ability to reduce your bulb’s energy use, without waste – plus they are quiet.