Types of Dimmers

                                                                                 Types of LED Dimmers

With the advent of LED technology more attention needs to be paid to the way light fittings are controlled.  Switching LEDs is very straightforward but dimming is a bit more complicated.  There are different ways of dimming (see below for the different dimming types) and the type of LED Driver needs to be matched to the control system in use.  It is also recommended to test drivers and dimmers together; even if theoretically compatible, they aren't always so in practice. 

Dimmers are devices linked up to a light fixture and LED driver(some dimmers are integrated the driver into the dimmer) in between which used to adjust the brightness of light. By changing the voltage waveform applied to the lamp, it is possible to lower the intensity of the light output. Although variable-voltage devices are used for various purposes, the term dimmer is generally reserved for those intended to control light output from resistive incandescent, halogen, and (more recently) compact fluorescent lights (CFLs) and light-emitting diodes (LEDs). More specialized equipment is needed to dim fluorescent, mercury vapor, solid-state, and other arc lighting.

 A lighting dimmer switch brings joy to many, and from an aesthetic point of view can stage-manage a mood and bring stunning dynamics to a space.

Imagine a dinner party with five layers of light and contributing to the sense of drama in the room or watching a film in the lounge room with lights dimmed low enough to eat whilst watching a film creating beautiful low light.

Dimming in an indoor or outdoor space not only controls the brightness in the space, but also improves the aesthetic appeal of a space, and saves energy. Dimmers range in size from small units for the size of domestic light switches to high-power units used in theatrical and architectural lighting installation.

A dimmer switch allows the operator to control the intensity of the light by emitting a pulse-width modulation signal that controls the voltage and current going  to a light. The dimming motion enables you to increase or decrease the intensity of the light.

All LED light fittings are dimmable. The challenge lighting engineers face is that the dimming signal has compatibility with the driver that is supplying power to the light. The most popular dimmer switch signals on the market today are phase signal (leading edge or trailing edge) / DALI / 1-10V.

Control Style Dimmer Switches:

Rotary Dimmers: They are the typical dimmer switches that enable you to control the lighting levels by simply rotating a knob. With the use of the dial/knob, you can adjust the light from dim to brightest. Rotary Dimmer Switches, a popular concept from the 70s and 80s, can have its dimmer switch wiring arranged in such a way that it can control the light from 1-3 locations.

Rotary Dimmers: They are the typical dimmer switches that enable you to control the lighting levels by simply rotating a knob. With the use of the dial/knob, you can adjust the light from dim to brightest. Rotary Dimmer Switches, a popular concept from the 70s and 80s, can have its dimmer switch wiring arranged in such a way that it can control the light from 1-3 locations.

Toggle Dimmers: Toggle Dimmer Switches, as the name suggests, shifts or toggles like the typical standard light switch. However, the level of the light automatically comes back to its previous settings.

Slide Dimmers: Slide Dimmer Switches slide up and down, are easier to manoeuvre and can be preset despite its slide design.

Rocker Dimmers: They are a popular favourite for home lighting solutions. They include a rocker switch that rocks up and down the light until it reaches the desired light level.

Tap Dimmers: These types of dimmer switches are perfect for smart homes, as they are compact and cost-efficient. They include a straightforward touchpad or button, enabling the user to preset their light level. Smart homes always lookout for smart switches and this is one of them.

Dimming methods

The following dimmer signals are:

Switched Mains  (Non Dimming)

If you don't need to dim your LED fitting then this is the driver type to choose. These drivers will work with conventional on / off light switches or lighting control systems.

Resistive dimmers 

These are broken up into leading edge and trailing edge.

Leading edge(mains dimming), This method of dimming is most commonly used for Electronic Low Voltage transformers typically used for Halogen lamps. Rarely used for LED fittings and frequently troublesome with LED.  No control cable is required. It's the most common type on the market and can dim standard incadescent lamps, low voltage transformers powering low voltage 12V lamps and constant current dimmable LED drivers. 

Leading edge dimmers are rated by the maximum recommended wattage it can dim. Overloading the dimmer can cause damage to the dimmer. This type of dimmer also dims constant current 230V dimmable LED drivers.  it can be used to dim most dedicated LED fittings when coupled to a mains dimmable driver. No extra control cable is required.

Trailing edge is less common, more expensive and incorporates added technology and features. Suitable for dimming are wire wound transformers, standard incandescent lamps, mains voltage halogen lamps and d immable LED lamps. A dedicated trailing edge dimmer (as opposed to a Universal type dimmer) is better suited to LED light fittings and gives very stable control of the light fittings on any specific circuit.

0-10V dimmers are directly linked up to AC mains and operate with the CFL and halogen and so on, saving a user from purchasing an additional LED driver to go with and suit the most anverage's house lighting control needs and no extra light retrofit works needed. 

1-10v Dimming

This method often works very well for dimming dedicated LED fittings when coupled to a 1-10V dimmable driver. Dimming is often smoother and lower than mains dimming options. It requires a separate ‘control’ cable to be run from the controller to the fittings driver.

DMX

DMX is commonly used for colour programmable fittings. The DMX signal is generated by a lighting control system and requires dedicated cabling between the controller and driver. DMX is generally used with professionally designed lighting control systems.

Zigbee/knx/dimmers are good for area lighting control. via a dimmer master, it will fulfill your group lighting control, creating lighting screnes, architectural lighting, individual/multiple groups light control. suitable for large area light dimming and control. It truely brings you a central control concept and allow you the light centralized control from a master controller.

DALI

DALI (Digital Addressable Lighting Interface) has been more commonly found in commercial environments and is a digital system. It is very flexible in its deployment and use. As with the 0-10V system it requires a control cable, but with DALI this cable can be run between many fittings. DALI is generally used with professionally designed lighting control systems.  We are increasingly using DALI in residential lighting projects for its superior dimming, flexibility, cost-effectiveness and simplified wiring structure.

Additional features that can be included in a trailing edge dimmer are soft start, smooth control, silent running and multi-method dimming. These features can all assist in extending the life of the lamps.

This dimming option gives you less control of individual lights if in a cluster. In a room of 6 downlights it is less expensive to set up and run. There are also a wider range of fittings that are compatible with that signal, thereby less expensive fittings and most importantly less expensive future replacement costs when the light globes blow.

Inductive dimmers

These are located on the secondary side of a low voltage or a lighting scheme. Inductive dimmers are rated by voltage rather than wattage. These are not suitable for home settings and are not found in the retail market.

Dimmer switch Vteck Lighting

Digital Addressable Lighting Interface (DALI) is a trademark for network-based products that allows you to control all your light fittings independently. It is generally used in conjunction with a home automation system or lighting control system.The programmer gives each light fitting a specific address and therefore each lighting fitting is controlled independently of the other.

As an example in a bedroom where you might have 4 downlights, you could control each of those 4 downlights independently. One is  at 100% and the other 3 at 50% power. By comparison, when using a lighting control system with phase leading edge or trailing edge dimming signal, all the lighting fittings on the one specific circuit are controlled together. All 4 fittings are either off or dimmed together.

Fluorescent light dimmers (1-10V)

Dimming fluorescent lamps is complex. To successfully dim a fluorescent light, a high frequency analogue 1-10 volt regulated ballast is required. There are some compact fluorescent lamps available on the market that will work with this type of dimmer.

Please note, not all lights dim the same. Different lighting brands perform differently. Some 'dimmable' lights will not dim much and could only dim in a 3 stage stagger, while others will dim to almost no light output with much gradation. Some will have a smooth change in brightness while others have quick jumps in their brightness as they are dimmed. The variation in performance between models and brands is generally quite large!

Do dimming lights save energy?

Yes- Light dimmers save energy by reducing the flow of electricity to the light and allow lights to operate with lower power output. Dimming lights also extend the life of your light source.

The amount of electricity sent to a particular light fixture is reduced. Therefore, the electricity bill for a light fixture is reduced anywhere from 40% to 90%.

Built-in dimmers

There are two types of built-in dimmers: rotary or push button. There are obviously different styles but designer dimmer switches can integrate beautifully into a wall. To turn lights on or off a rotary knob dimmer is pressed. You turn the knob to select the light intensity.

A push-button works according to the same on-off principle. However, to change the light intensity, you must hold on the button. Some push-button dimmers alternate in their operation (brightness increases during the first long press, dimming occurs during the second long press). Other push-button dimmers reach a specific percentage of brightness. 

What are light dimmer location options?

Dimmers typically come in three location options:

Single-pole dimmers are designed to provide dimming control from only one location.

Three-way dimmers adjust the lighting levels of your space from one location, but are installed with three-way on/off switches allowing you to turn the lights on to the dimmer level from a variety of different locations.

Multi-location dimmers are typically paired with accessory dimmers that allow you to fully control and dim the light output from multi-locations.

Internet-enabled dimmers

There are manual and internet enabled dimmer switches where you can adjust energy output, light intensity from your phone in the form of an app. The more expensive dimmer switches often include features such as sleeker design and integration with smart phones. 

What are the compatibility issues with dimmers?

Phase signal dimmers can have issues if the load on a specific circuit (the number of fittings on that specific circuit and therefore the power draw of the circuit) is very low. Low power draw causes light flickering. Light flickering is resolved by the use of a load correction device that is retrofitted by the electrician to artificially increase the load on that specific circuit and thereby stabilise the power and eliminate the flicker.

Legacy technologies when converting old halogen lights with LED fittings is one of the biggest challenges. An example of this is a typical halogen downlight has a 35W or 50W halogen globe and iron core transformer. The technology uses too much energy to deliver the light source. Modern LED downlights only draw 6W per fitting.

Understanding the different dimming types is critical to the success of any lighting project.  As part of our lighting design service we can supply lighting control systems with matched drivers and dimmers

When taking a halogen fitting and installing a LED light fixture the load on the circuit is significantly reduced. Transformers and dimmers need to be changed to the new technology. Do not mix dimming circuits from different manufacturers as you may get flicker, stuttering dimming and rushed dimming.