LED DALI lights with DALI driver
Why is DALI experiencing an increased demand due to the introduction of LED technology? It is simple. If you want to dim LED lights, you can not get past an electronic control unit.
Previous conventional luminaires have been equipped with light sources such as incandescent lamps, halogen lamps, fluorescent tubes or fluorescent lamps. Although the latter were no longer quite as suitable for dimming, commercially available wall dimmers with trailing/leading edge control via triac or MOSFET could be used.
These were developed in the age of the incandescent lamp / halogen lamp and were ideally suited for controlling the brightness.
LED lights require a LED driver
To operate LEDs, a constant current is required which prevents the LED from being overloaded. This special electronic ballast (often also called LED ECG) needs 230V mains voltage on the input side and cannot even do anything with the "bent" alternating current sinus of a dimmer.
Attempting to do this may result in the following behavior, depending on dimmer and LED driver:
But there are LED lights that are dimmable as usual ...?
Correct. These contain an LED driver that was developed for use with wall dimmers. The TCI Jolly MD dimmable should be mentioned here in particular, which, depending on the jumper setting, can be dimmed via trailing edge dimmers in addition to 1-10V or push-button operation.
The manufacturer has managed to ensure a broad compatibility.
But even here it is not possible to regulate the light evenly down to 0% brightness. This is because the driver also needs a residual voltage for safe operation.
The solution is called LED DALI control
DALI as control bus for the transmission of various signals from central to all connected luminaires as "circular command" or individually addressable enables convenient control of luminaires. Of course, this also includes a complete dimming of the brightness over the usual range.
In addition to the dimming function, the control of LED luminaires via DALI also makes it possible to program each individual luminaire centrally and assign it to different groups. In such a way that the planning of circuits on individual light switches is no longer necessary. This can be individually adapted to the respective situation at any time and also afterwards. Examples are open-plan offices or warehouses, where the lighting situation often has to be adapted for organisational reasons.
In short, LED lights only dim DALI. That is easy with e.g. a LED driver DALI
Transmission of DALI signals - how?
If a building is newly installed, it is recommended to plan the lighting installation including the DALI bus from the beginning. That is simple. Instead of three-core cables, five-core cables are now laid throughout. What is connected to it and whether it is used to its full extent does not matter. It is completely flexible with DALI bus. Due to the "slow" data stream, a "chaotic" wiring is possible. This means you do not have to pay attention to star, circle or chain connection. It may be wired identically to the 230V wiring as required. Even the polarity of the DALI lines is irrelevant.
But how do I do this with DALI in existing buildings?
Who would want to knock open the walls and lay new cables in a beautiful old villa when converting to LED with DALI? Surface-mounted wiring is also not desired.
There are Enocean radio solutions for this which, via a gateway with built-in DALI controller, enable fast and convenient installation without large additional wiring from the light switch to the LED luminaire.
1-10V control as an alternative for DALI LED
The analogue control is still used with a 1-10V potentiometer. The ballast in the luminaire receives a voltage between 1V and 10V at a special control input and controls the brightness of the luminaire accordingly. This 1-10V input on the ECG is potential-free. A distinction is made between active and passive connections.
- Passive 1-10V input --> Control via external control voltage
- Active 1-10V input --> A potentiometer with which the voltage can be regulated via the internal voltage divider is sufficient.
Conclusion on LED with DALI
DALI is attractive again. The demand for DALI devices, especially the DALI-USB-Adapter as a link between LED lights and the computer with DALI Master PC software, is increasing. If you want more than just switching light on and off, DALI is the standard solution today.