Here you will find answers to questions concerning Lighting Control Systems. If you have any questions, feel free to call our team on 0117 325 0063 or send us an email if you’d like a subject covered.
Lighting control systems control lights across a space or building. Control systems can be used to allow simple robust control from a scene setting keypad or a web/phone/tablet application. In the case of the Prodigy Series, we’ve made it very easy to take control of all instances of Prodigy by using our finder application (searches and brings all instances on the network under your control. There are vast number of advantages to using a control system. Lights can be programmed to be used only when required. This means that your lighting can react to the provision of natural light and the presence of those who need the light. Further to this, scenes can be setup so that you can very the lighting levels and temperatures to suit the mood you are trying to create or to turn a workspace into a break-out space.
DALI is a two-way communication protocol, utilised in digital lighting technology. The DALI Protocol defines a set of commands that provide control of LED drivers and ballasts. LED drivers and ballasts send information back to the user via the DALI controller, appropriate software or building management systems. In the case of a 0-10V system, communication is uni-directional, with the control system telling the LED driver or ballast what to do, adjusting according to the voltage on the control circuit. DALI, in contrast provides a two-way method of communication, giving the LED driver or ballast a chance to ‘talk’ back.
In a DALI system the LED drivers, ballasts and a central controller are connected together via a two-wire bus. 64 individually addressed devices can be connected to the bus and controlled. Multiple devices can be controlled simultaneously by grouping them together through the controller.
DMX, also known as a Digital Multiplexing communication protocol. All luminaires in a DMX system are run through a single control panel. DMX's versatile control capabilities are particularly advantageous in theatre and concert, where there is heavy use of moving and colour changing lights. DMX enables the digital control of individual fixtures via a low voltage communication protocol but allows for a larger range of digital addresses via a DMX universe (512 unique addresses). DMX enables the control of light colour, a feature not possible with DALI and one of several differences between the two control systems. Our Prodigy Lighting Control System (viewable here - https://www.gds.uk.com/products/prodigy-controller/) is an example of a DMX Dimming System.
The main differences between DALI and DMX are as follows;
• DMX is a fast control system, whilst DALI is a slow speed control system. This is due to the fact that DALI is a reactive system (i.e. it responds to the user’s actions, whereas DMX can be pre-planned)
• DMX has up to 512 channels, compared to DALI’s 64.
• Automatic addressing is not possible for DMX, but it is possible for a DALI system.
• DMX requires additional cable cores (minimum of 3) and line termination. This makes DALI great for areas where wiring is not crucial (i.e. commercial foyers).
• DMX is controlled through a centralised panel while DALI can be a decentralised control system. • DALI can utilise sensors to make it react to the changing environment
• DALI can take control of its 64 channels with a ‘broadcast’, DMX cannot do this.
• Synchronised changes. DMX streams which means level changes are always synchronised. For DALI, changes are synchronised if they result from the same instruction. However, because of the 16-scene limitation in DALI, control systems often rely on sending individual set-level commands, these are not synchronised and can create a staggered effect.
• DMX is renowned for its reliability and responsiveness, with the flexibility to control more than just lighting. As such it is the industry standard and any product making use of DMX can be used together within the same system.
A controller designed to operate with devices that respond to the DMX or DALI protocol, that can store, record and recall lighting scenes.
In order to understand smooth dimming, we must first look at what within traditional dimming methods causes unsmooth dimming. One of the first issues with traditional dimming was that controls didn’t allow for small incremental changes. This meant that light output could be changed by 5 to 10% as a minimum (this results in a noticeable change). For smooth dimming the change should not be perceivable to the human eye. Another cause of unsmooth dimming is the ability of the human eye to perceive light. The eye cannot perceive a linear relationship between light energy and brightness. As light in a space continues to increase, a person notices less and less of change. This a consequence of ‘pupillary response’ which is the iris contracting to receive less light as it grows in the space. Therefore, any dimming must factor this in if dimming is to be perceived as smooth.
The dimming of LEDs will extend their lifespan and brightness. This is because LEDs tend to get dimmer as a result of heat and dimming reduces the LED's heat, ergo the lifespan is extended.