Do you need a dimmable power supply with RGBW LED strip lights?

Do you need a mains dimmable power supply with RGBW LED strip lights? A: No!

This is a question that we get asked a lot.

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When we quote an order for colour changing LED strip lights, our description for the power supply says ‘non dimmable power supply‘. Yet the customer is looking for dimmable RGB / RGBW / Dual white  LEDs!!  Why does it say non dimmable!!

Well, that’s because any strips that offer colour changing functionality (such as  RGB /  RGBW or dual white LEDs) actually need a ‘controller’ to control them and not a mains-dimmable power supply. Mains-dimmable supplies can, in fact, only be used for white or single colour led strip lights.

Colour-change controllers require a constant 12v/24v from the power supply, not a varied power supply (dimmable).

We actually call this parrt of the LED installation a ‘receiver’, as it receives signals from a controller to tell it what the lights should be doing.


for colour changing lights, your installation would always follow this general wiring sequence:

240v mains supply ——->  Non dimmable 12v/24v power supply ——–>  Receiver box  ——> LED strip lights

All controlled via a remote or wall controller etc.

(The controller sends a signal to the receiver to dim the lights.)

So for your project you would have the power supply and a mains on/off switch only. You would then dim the lights using whichever controller you have chosen.

All of InStyle’s controllers remember their last colour/brightness setting when powered on/off from the mains switch, so you can set a dimming level and it will be remembered next time you switch your LEDs back on.


This is also called ‘dimming on the secondary’ as you are dimming on the output side of the power supply, rather than dimming on the primary side (the 240v side).

For an example, please see here:

Why InStyle LED?

We stock all of these LED strips for next day delivery.

You can provide us with the lengths or, even better, a quick sketch of your area with the lengths written on them and we can advise the best way to wire the strips.

We can speak to any installers, before, during and after your project to answer any questions.

Please call us today on 0116 2799083 or email [email protected]