Choosing a LED driver for your LED Downlight

29 December 2022
choosing_a_led_driver_for_your_led_downlight

Selecting the right LED driver for your LED downlight can sometimes be more difficult than you would otherwise think.

There are two things that you need to know before you start looking:

  • The required output type
  • The required dimming type (if applicable)

Let’s take a look at the output type first.

LED drivers fall into one of two categories; Constant Voltage, or Constant Current.

Which one you need purely comes down to the design of the LED downlight in question.

Most LED downlights require a constant current LED driver, though there are a few that require constant voltage.

If the LED downlight has integrated electronics to regulate the current being fed to the LEDs, then it will require a constant voltage LED driver. 

As well as identifying the output type required, you also need to know the required output value.

For example if you need a constant voltage LED driver do you need 12V or 24V? If it is a constant current LED driver you need, is it 350mA? It could be higher or lower than this, but you need to know either way.

If you are replacing an existing LED driver, then you can check the output details that are printed on the LED driver you are replacing.

If you are not replacing a LED driver, then you will need to check with the manufacturer on the required current / voltage required to power the LED downlight. This may be stated in a product data sheet, or you may have to ask the manufacturer directly.

If you don’t need a dimmable LED driver, you can go ahead and start looking for a suitable LED driver.

However, if you need a dimmable LED driver you will need a LED driver that is compatible with the type of dimmer being used.

In most domestic situations you will probably have a TRIAC type wall plate dimmer. These are connected across the AC input into the LED driver and work by chopping the AC power being fed to the LED driver. If you have this type of dimmer, then you need a LED driver with AC phase cut dimming.

The MEAN WELL PCD LED driver incorporates the AC phase cut dimming feature.

MEAN WELL PCD-25 LED Driver
MEAN WELL PCD-25 LED Driver

 

You may not be able to find an AC phase cut dimmable LED driver with the required output type. In such cases, you may be able to change your dimming control for a 1-10VDC dimming pot.

LED drivers that feature MEAN WELL’s 3-in-1 dimming function will work with a 1-10VDC dimming pot. They will dim down as far as 10% of the rated output and need a separate on / off switch.

This is because the 1-10VDC dimming pot has to be wired to dedicated dimming terminals, or wires on the LED driver. The LED driver has an inbuilt dimming control circuit which takes the 1-10VDC signal and adjusts the light output accordingly. The on/off switch is require to turn the AC mains on and off as required.

One or more of the MEAN WELL Australia partners listed on this website sell 1-10VDC dimming pots and they will fit in most existing wall plates.

MEAN WELL has a wide range of constant voltage and constant current LED drivers that feature the 3-in-1 dimming function.  You can browse the range on this website, but please don’t hesitate to contact MEAN WELL Australia if you are struggling to identify a suitable LED driver for your LED downlight.

Another thing to be mindful of is dimmable LED drivers with a PWM style constant voltage output. The output of these LED drivers is being cycled on and off very rapidly and the integrated electronics of a constant voltage LED fitting can struggle to keep up with the switching frequency of around 1.5Khz. You may be better off using a type that dims by varying the amplitude of the output current.

Please contact MEAN WELL Australia if you require assistance looking for a suitable LED driver.