Power Supply for LEDs - everything about LED Drivers
LED modules can only light up if the necessary power is supplied to them. This also applies to our FLUXengine and APEXengine LED Boards. On this page we explain the basics of LED drivers and show what you should consider when choosing a LED driver. This page is especially for our FLUXengine DIY LED modules, but the basics apply to all LED applications.
Basically, any power supply unit can be used as a power supply for LEDs - provided that the parameters are correct! However, special ballasts for LEDs, also called LED drivers or constant current sources, are better. These ensure that a constant current is driven through the LEDs regardless of the forward voltage of the LED. They thus enable safe and flicker-free operation even with fluctuations in the mains voltage.
Mean Well LED Drivers
We recommend Mean Well LED drivers for our FLUXengines and APEXengines. Since 1982 the Taiwanese manufacturer stands for an excellent price-performance ratio and reliable products in the field of power supply.
The correct LED driver can be found by using the Select a model with the appropriate specifications according to the data sheet.
Mean Well Driver Series
For constant current sources for LEDs the series HLG and XLG, as well as ELG are especially recommended. In our kits we mostly use the new XLG power supplies. Their innovative constant-power mode allows for maximum flexibility when expanding. It is often possible to increase the illumination area without having to change the driver.
If you are planning to use a higher powered LED system, you should opt for the HLG series, as these high-end units offer the best efficiency. The XLG and ELG series are less expensive, but do not need to hide behind the economical operation. In most cases the XLG and ELG drivers are only a few percentage points less efficient than the HLG products.
Connecting LED modules to the driver
LED Drivers for FLUXengine and APEXengine Setups
In most cases it makes sense to use different drivers for FLUX modules and APEX modules. The two types have very different limits for the current flow.
By combining series and parallel connection it is possible to implement a mixed setup. However, the ratios in the combined spectrum are then fixed. The advantage of a single constant current source per channel is that you can adjust the light spectrum to the needs of the plant by selective dimming.
Mean Well Driver Dimming Operation
Types A / B / AB
The Mean Well power supplies are available in different versions, which differ in their dimmability. With many models the variants are marked with suffix -A, -B or -AB specified in the manufacturer's designation, e.g. XLG-240-M-AB.
A - Internal Potentiometer for Current Limiting
Products with the A suffix feature a potentiometer built into the device. This is hidden behind a splash protection cap in the housing. A screwdriver is required to adjust the current or voltage. The control range of the A models is limited to 50-100% of the maximum current. Due to these limitations, this is not actually a dimming function for frequent operation - rather it is intended to limit the current as required.
B - Externally Dimmably via 3-in-1 Dimming Function
The MEAN WELL power supplies with B-suffix have a second pair of wires at the output marked DIM+ and DIM-. There are three ways to obtain a dimming function.
- Resistance: The simplest - particularly suitable for DIY projects - is to connect a resistor between the DIM+ and DIM-. A potentiometer can be used for this purpose - a rotary knob that can variably change the resistance. For one power supply you need a potentiometer with 100KOhm. It is also possible to dim several power supplies with one potentiometer, but this requires a different potentiometer, e.g. 50kOhm for two power supplies etc.
- 0-10V Voltage: A standard signal that can be output by many control units. Also with the CresControl this function is used. Many dimmer switches installed in buildings rely on a 1-10 V signal to dim lamps. This is also supported by MEAN WELL power supplies. However, further measures are then necessary to switch off the lights completely.
- PWM: Pulse width modulation (PWM) is a digital signal that the LED drivers can interpret. Especially useful for handicraft projects with Raspi, Arduino and Co.
The advantage of the B variant is not only that the dimmer can be placed anywhere and the operation is much more convenient. But also the control range is significantly larger. The LED driver can usually be controlled with external dimmers from 0-100 %, i.e. "dim-to-off", so that only a low standby power consumption is available.
AB Version: The Best of Both Worlds
The name almost suggests it: Drivers with AB suffix have both the internal potentiometer and the wires for external control of the dimming signal. This is the most ideal solution and we therefore always offer this variant when it is available.
Instead of using professional measuring tools, the maximum current can also be set with a "consumption meter".
- This is connected between the socket and the load to measure the power consumption.
- Before switching on for the first time, the potentiometer (adjusting screw) I(out) on the driver is set to the lowest value (turn to the left).
- After switching on, I(out) can be slowly increased (turn to the right) until the "consumption meter" shows the desired power.
- The permissible power ratings of the individual components (especially LED drivers and LED modules) must be observed.
Mounting LED Drivers
The LED driver can be mounted on the frame or heatsink or can be placed elsewhere. To keep the grow environment cool, it is recommended to place the driver e.g. outside the tent.
Mounting on the Frame
If you want to connect the driver to the frame, you should thermally decouple it. We include plastic washers with our kits that make it easy to create a small gap between the driver and the heatsink to minimize heat transfer.
The good thing about in-house solutions and DIY LED projects is that you can adapt the lamp to your individual ideas. If required, we can supply longer wire leads so that the driver can be placed away from the mounting environment and no additional heat is introduced into the box. Just write in the comment of your order how many meters you need extra. We will try to meet your request.