Over these past years, we have seen how LED technology has come to dominate the lighting market at a dizzying speed, to the detriment of the use of several different conventional light sources. This has had the effect of accelerating their gradual disappearance. However this technology has brought benefits with it in terms of energy efficiency as well as the possibilities it offers as regards dimming and control. This fact, among others, responds to a growing concern of consumers to achieve an efficient, quality lighting that adjusts to their needs at any given time.
Combining all these concepts, ELT has developed two series of drivers to supply LED modules that incorporate the latest advances in dimming and control techniques while offering cutting-edge features and optimal energy efficiency, thereby making them suitable for the most demanding of indoor applications.
Possible applications for the new series of indoor drivers.
Both series are available in two different formats so they can be correctly adapted to the type of application or lighting fixture.
Available formats for the new series of indoor drivers
Several output currents are available for each series. This current can in turn be adjusted in small increments of 25 mA, by means of an integrated micro switch that can be adjusted to the various supply values of most LEDs currently on the market.
Output currents and available models for the DLCM-E-DALI series.
Ongoing improvements to the efficiency of LEDs inevitably results in a reduced supply current to achieve a light solution that equals the previous system. By integrating this series of drivers, such evolutions can be offset when developing LED chips, avoiding the need to change the lighting fixture documentation or model used. All that has to be done is make a minimum adjustment to the micro switch during the productive process to slightly reduce the driver's output current.
Detail of the integrated micro switch
They also offer an extensive dimming range (from 3 to 100%), providing great flexibility when adjusting the lighting to any situation, for example, dimming the lights while we are watching a film which avoids the eye strain caused by receiving light from the television alone.
The extensive dimming range is able to adjust the lighting to any situation.
Internally, output current modulation takes place by means of the method known as Pulse Width Modulation (PWM). As such, the LED modules are always powered with the same level of current, only varying the time each cycle is ON (duty cycle), depending on the preset dimming level.
This type of modulation avoids colour variations in the LED module: given that they are always supplied at the same current, there are no variations to the emitted wavelength. In addition, by using frequencies of several hundred hertz, the strobe effect, that makes us see bodies in motion as static, is avoided.
To clarify, we need to distinguish between the output modulation method and the type of regulation of the LED driver. The first refers to the way in which the driver output varies (by level/analogue, PWM, hybrid….), while the second is the type of input signal received by the driver and via which we communicate with it (0-10V, 1-10V, DALI, PWM, DMX…). Both elements are independent, so we are able to have a driver with one type of PWM input regulation whose output modulation takes place by level.
DALI input control signal (DA/DA) and PWM modulated output current (+/-).
These devices have a low level of output ripple current (ORC), which provides a high quality light, reducing visual fatigue and a range of adverse effects that are caused to human beings due to exposure to light sources with high levels of ORC. Some such effects currently being studied, including reduced performance, epilepsy and general ill health. This quality makes them the perfect devices for installations in which people are subjected to artificial light exposure for hours on end, such as in offices and schools.
They moreover deliver excellent efficiency and electrical features (low levels of total harmonic distortion or THD, and a high power factor), while providing a high level of protection against anomalous situations such as short circuits, overloads or vacuum operation. They also integrate thermal dynamic protection by means of which the power supplied gradually reduces if the device’s maximum temperature values are exceeded.
Thermal dynamic protection operational flowchart.
Having highlighted some of the features shared by both ranges, here is an analysis of the functionalities inherent to each:
DLCM-E-DALI
This product range is compatible with the DALI (Digital Addressable Lighting Interface) protocol, which is a digital and addressable communication interface for lighting systems.
Wiring diagram (DALI).
Logarithmic dimming curve (DALI).
Apart from this communication protocol, the system incorporates the following features:
Touch control:
This is a system through which the light flow is simply and economically regulated, using the grid voltage as control signal, applying it by means of a standard push switch that is normally open on a control line with no need for specific controllers.
It is able to perform the basic functions of a dimming system thanks to the action of a potential-free push switch. The lighting is turned on and off by means of a short press or 'click', while by means of a long press and hold, the light flow is regulated alternately between the maximum and minimum levels.
Wiring diagram (TOUCH).
Dimming curve (TOUCH).
Función corridor:
This function is able to control the light level by means of a conventional motion sensor connected to the DALI terminals. When the sensor detects presence, the light level increases by 100%, otherwise the driver maintains the light level at 10%.
As a result, the lighting is only activated when needed. It also ensures that it is never completely turned off, maintaining at least at a minimum light level. This last point is extremely useful in certain installations, for example in a hotel corridor.
Corridor mode operating mode.
DLCM-E-BT
This innovative series of LED drivers belongs to the range of eBLUE devices and enables wireless lighting control via a simple and intuitive app that uses Bluetooth Low Energy (BLE) connectivity for smartphones and tablets.
Along with the DLCM-E-BT series, lighting can be controlled to create the desired setting very easily. From your smartphone or tablet, the level of your lighting fixtures can be adjusted; existing wall switches can control different settings; and presence detectors activated. It also enables a fully automated and autonomous lighting system, with no need to add any extra device or wiring. It is clearly a new lighting experience.
eBLUE technology operational diagram.
Below we highlight some of its most important features:
Easy and intuitive first time use:
The app is able to control every luminaire that has been equipped with eBLUE technology. Set-up is simple and intuitive: all you need is one simple click to start controlling all your lighting.
Control all your lamps via the same interface:
You can control all your lamps from one screen. Control can be individual or by groups. For example, you can create a group with the lamps in your kitchen, office or shop, so that they can all be turned on and off with a single click. You can also regulate their light levels by swiping your finger over the required lamp or group.
It is the simplest and most natural way to control your lighting:
Take a photo of the room and position the room’s lamp controls on the photo. Now you can control the lamps visually from the photo of the room itself.
Create scenes for different situations:
Set the appropriate lighting for a dinner, office environments or shop promotions and then save the configuration as a setting. Now you can change the lighting with one single click to adjust it to each one of these situations. Animated scenes can also be created that comprise several settings. For example, these could be used to automatically and dynamically highlight products in a shop window during the night.
Old switches made smart:
The innovative Smart Wall Switching (SwS) function, allows conventional wall switches to be used as dimming switches or to control settings. As a result, you can control all your lighting from one single switch.
Automated lighting control:
It is possible to create a list of events that activate or deactivate settings or animated scenarios depending on the time of day. For example, you can activate the lighting to wake you up in the morning or establish a savings profile for office lighting.
Share your network and let other devices control your lamps:
There are four different levels available to share and control access to your network. You can decide if your network is open to everyone or if a password is required to access it. In the event that several users or devices are using the same network, any change made by any user will be automatically updated in every other device via the cloud.
As we commented at the beginning of this article, the world of lighting is undergoing a complete process of transformation. We are not only talking about improvements to the efficiency of the light sources, but also an enhanced quality of that light, its adaptation to every situation as well as its options for control, and of course their connectivity which is able to connect a group of lighting fixtures to the power grid.
We believe that lighting is now in a position to offer the ideal platform that will support the Internet of Things (IoT) and Smart Cities over the coming years. The lighting sector will play a leading role in all these developments and ELT will continue to work to create products that prepare us for an increasingly more efficient and connected future.
Adrián Garcés - Ingeniero I+D+i
