Problems with Matching LED Drivers to LED Downlights

Installation Advice

We often receive calls from customers who have installed a new LED driver to power a LED downlight, only to discover that they have problems.

The LED downlights may flicker, flash, be too bright or too dull.

A common cause is often a mismatch between the LED driver purchased and the type of LED driver the light fitting needs.

Many LED downlights have integrated electronics to regulate the current being supplied to the LEDs of the fitting. Usually, such downlights will require a constant voltage LED driver.

If the LED driver has a PWM output this can cause some incompatibility problems between the driver and the light fitting.

Duty cycle of MEAN WELL PWM series LED driver — PWM Duty Cycle found on the output of some Constant Voltage LED Drivers

The most common cause of incompatibility is the PWM output. The output of the LED driver is actually 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.

If a LED downlight has internal regulating electronics it is preferable to test a PWM driver with the fitting before installation or use a constant voltage LED driver without a PWM output.

ADM stocks a range of LED drivers, including dimmable models that do not use a PWM output.

If you would like help in selecting a suitable LED driver, please contact ADM. A member of our expert team will gladly answer any questions that you may have.