How to Dim Meanwell LED Drivers

This guide details how to adjust dimming on Meanwell LED Drivers. The information below is for design purposes only, and is not a safety guide. Please use proper electrical handling techniques when working with live circuits.

Understanding Meanwell LED Model Names

Meanwell LED driver model names start with the Series Name (HLG, XLG, etc.).

The second group of letters and numbers indicates the power output (120W, 240W, 480W, etc.).

The third group indicates the rated output voltage or current. This is a maximum value, and is important for selecting a compatible LED driver for your application.

The fourth group indicates the dimming operation style.

Determine Your LED Driver Dimming Type

To determine the dimming type on your Meanwell LED driver, look at the last letter in the model name listed on top of the driver unit.


Meanwell LED drivers come in many varieties. The most commonly available types are:

Blank Type: This model has no dimming adjustment capabilities, and only outputs the full rated power.

A-Type: This model has two internal potentiometers; one potentiometer adjusts the output voltage, while the other adjusts the output current from 50-100%.

B-Type: This model has an external dimmer lead and offers 3 dimming modes. The driver output can be adjusted with providing resistance, PWM signal, or 0-10V across the external dimmer leads.

AB-Type: This model has both features of the A-Type and B-Type.

Adjusting A-Type Drivers

To adjust A-Type drivers, you will need a small Philips head screwdriver (size PH1).

Step 1: Remove the small rubber cap covering the "Io" adjustment knob.

Step 2: Use the Philips screwdriver to turn the internal knob. This will adjust the output current of the driver.

The adjustment holes on the drivers are lined with a plastic sleeve; however, do use care when inserting the screwdriver.

Adjusting B-Type Drivers

To dim B-Type drivers by applying resistance, you can use a 100K potentiometer.

Atreum Lighting offers an encased dimmer module (External Dimmer with Knob).

Attach the dimmer by connecting the positive and negative leads to the respective leads on the LED driver. Note that Meanwell LED drivers may use different color leads between series, so it is important to double-check the label on the LED driver.

Polarity Dimmer Module Meanwell LED Driver Dimmer Leads
Positive (+) Red (As labeled)
Negative (-)  Black (As labeled)


Turn the knob on the dimmer module to increase and decrease the LED driver power output.