The dimming capability of Aqualux products is determined by the control gear code and power source.
 

Selecting the right option is important if you require a form of dimming for your lighting system.
 

To determine Aqualux dimming compatibility, locate the control gear code ‘B’ in your product code. 
 

Refer to the table below to determine the dimming capabilities and what control gear is needed.

PWM power dimming directly modifies the output of a power supply via PWM (Pulse-width modulation). It controls how often the current is on or off hundreds of times per second. 
As the human eye cannot perceive frequencies this fast, the effect is an apparantly stable variation of the output light level. 

PWM power dimming can be achieved by using compatible power supplies that will require their own dimming control input. It can also be achieved by using a PWM module that sits between the power supply and lighting product and modifies the power to control the PWM dimming. 
PWM Power dimming is common in LED strip lighting products and operates across any number of channels (eg. White, Tuneable White, RGB, RGBW).

The benefits of PWM power dimming are that it is relatively straightforward requiring no additional wires, that it works independent of the load rating of the power supply and that it does not require additional signal wires.
The drawbacks include that the LED forward voltage must be closely matched (linear) with the power supply voltage - Many discrete LEDs require voltages that are not common and are difficult to control in a linear fashion.
This is why PWM Power dimming is most commonly used with LED Strip lighting type products where multiple LEDs can be combined to create a 12V or 24V LED circuit.

PWM Signal dimming directly controls the output current of a power supply, either an internal constant current driver inside a light fitting or an external constant current or constant voltage power source. 
The driver or power supply requires a separate control signal wire that the PWM signal is delivered over. The PWM signal is then used by the driver to modify the output current to the LED. 

The advantages of this approach are that multiple individual fittings can be controlled with the same dimming signal and that it operates independent of the internal LED voltage. A variety of types of fittings can be controlled in the same manner. 
Many other forms of lighting control are in fact interfaces to a PWM Signal type of dimming, given that close to the LED a PWM signal of some sort will almost always be needed to modify the LED output. 
 

DALI (Digital Addressable Lighting Interface) is a modern lighting control protocol. It allows each device to be individually addressed and controlled. 
The benefits of DALI are relative ease of deployment and commissioning, with each fixture or driver assigned an address and independently controlled.

The drawbacks include the requirement for additional components such as a DALI power supply and typically a master controller.  Additionally, DALI wiring rules specify that the control cables (although ELV) must be treated as 240V.
This simplifies wiring in mains powered lighting systems but may complicate requirements in SELV systems. 

Aqualux fittings that are DALI compatible typically use a DALI/PWM interface to provide this control. This means that control is available down to the power supply group rather than individual fitting.  

DMX (Digital Multiplex) is a common digital protocol for the control of entertainment lighting and architectural systems. 
Developed initially for linking theatrical lighting and effects systems to central controllers, it has expanded to include many other functions.

DMX requires a separate set of control cables to carry the data signals from a central controller to the lighting control systems and power supplies. It can be used with both low voltage and mains lighting products as the control system is completely separate from the lighting power supply system.

The benefits of DMX512 are that it is a widely used and well-understood system with many compatible control products. Very long signal cable runs are also possible, up to 1km or more. Wireless DMX equipment is also available. 
The main drawback is that DMX requires additional control equipment and adds complexity to a system beyond what is typical for residential applications. Many fittings will also require an interface module to convert the digital DMX512 signal to PWM signal.

Phase cut dimming includes both TRIAC-based dimming (leading edge) and trailing edge approaches. 
There are also “universal” dimmers that can determine the most appropriate mode for the detected load. The benefits of phase-cut dimming are that it is simple to install and widely understood by most contractors. 

The drawbacks include incompatibility with many LED products and varying performance that depends on the combination of dimmer, power supply, and LED light.
Some manufacturers recommend only certain combinations of dimmers and power supply units.

There are a growing number of mesh network protocols intended for wireless control of lighting and other building systems. Casambi and Silvair operate using Bluetooth mesh networks, whereas Zigbee utilises its own radio communication method.

Casambi in particular is growing in popularity and Aqualux will soon be able to offer a range of options for control of fittings and strip lighting with Casambi products. 

ArtNET is a protocol for transmitting DMX/RDM signals over Ethernet. It can make the deployment of a DMX solution a lot easier as it can utilise existing infrastructure.