12. June 2017

Duex5 – Use build in 12v switching regulator on 24v system

By BeTrue3D


Use Duex5 to get 12v

As far as I know the Duex5 (also in Duex2) is the only Controller or Expansions -board for 3D Printers with build-in 12v switching regulator, which means you can easily get 12v even if you use a higher voltage to power your machine (VIN Power – opens Duet3d Glossary) without having to restort to various step-down modules lying around in or outside your printer creating potential for shorts and other errors.

Jumper Settings

In order to activate this 12v switching we need to:

  1. Put a jumper on the pins marked with nr. 1
  2. Check the FAN jumper nr. 2 is placed on the 12v position
  3. I’m going to use the FAN3 Connector marked with nr. 3 for my LEDs

In case you have difficulty seeing the colors as me, being colorblind, the + wire is to the right side of the 2-pin connector, and – wire on the left side.

Image is part of the original conenctions diagram on Duet3D wiki.

You can also see the full diagram here:

Configure LED in firmware

We really just need to open the Config.g file and insert a small line under the other fans in our FAN section, like this:

M106 P3 S1; Set fan 3 value for our LED to on.

It really just put FAN connector 3 on full power.

Further customization options

We can put the power to the LEDs on half (dimming it) by setting S to 0.5 instead of 1, or use the 0-255 range if that’s more to your liking.

It also means you can control it using Gcodes to do different things like turning LED on when a print starts and turn it off when a print job ends or what ever you like.

All done

Here you can see the new jumper on nr 1, set jumper on nr 2 and our LED connector on nr. 3