When building CNC systems, one thing is guaranteed. You are going to need at least one power supply.  Many times more than one.

I want to take you through some of the power supplies that I use on a regular basis and how I connect them to my DIN rail system.

DIN Rail Enabled Power Supplies

These are two power supplies that I used to power ancillary equipment, like fans, controllers, or the other logic boards.

They don't output enough current to run most CNC drivers.

The first is a 12V, 3.3Amp, the second, a 24V 2Amp power supply.

Both have built in DIN rail support and screw terminals for 110-240v AC input and multiple screw terminals for the DC output.

Both have adjustments so you can tweak the voltage.

If you need a little more power on the 12v side I have also used this 12V 5Amp power supply.

These smaller DIN rail power supplies are fairly reasonable in price, but as the power and voltage goes up so does the price.  More so than non DIN rail power supplies.


Non DIN Rail Enabled Power Supplies

Here is a very large power supply that I use to power the G540 and the stepper motors on the KRMx02.

It's a 48V 12.5 Amp power supply.

If you can find a DIN rail equivilant its going to cost you at least twice as much as a non DIN rail power supply.

In order to mount this one, I added some small DIN rail mounts that I printed on my 3D printer.

Please note that I will be going over these mounts in seperate write-up.

Often you need to power a logic board. This could be a SmoothStepper, Stepper Driver, or breakout board.

This is a 5V 5 Amp power supply.  I use them all the time and they are very inexpensive.

Again I just attached it to a small 3D printed DIN rail mount.

You can also use open frame power supplies.  They don't have an enclosure but can easily be mounted on a set of DIN mounts.

This is a small Dual 12v/5v power supply. I use them to power logic boards and muffin fans.

You can get one here:

Dual voltage power supply board

Something I started using more and more are these little Buck converters.

This one can take a DC input voltage in the and drop it down to an adjusted voltage.

Its rated at 3-40v DC input and 1.5-35V 3Amp output.  They are very inexpensive and are sold in sets of 6 for under $12.

You can get a set here:

DC-DC Buck Converter

You can power these from other power supplies that you have mounted on your system as long as you don't go over the maximum input voltage.

I had a CNC system that used a 24V 15Amp power supply to power the drivers/motors.  I used one of these buck converters to get a 12V 3Amp power source and a 5V 3Amp power source.  

Cost me $4.

Here are a couple buck converters I have used to power some other devices.

The first is a small buck converter with a builtin voltage display and terminals.

The second is the buck converter mentioned above. I just added a small voltage readout.

Note that these are light enough and small enough to mount on the side of an existing power supply.  Just make sure you use some sort of thick double sided foam tape to insulate them from any metal surface.

Double up the foam tape just to be safe.

Here is something I just threw together. It consists of a 3Amp buck converter, Voltage monitor, and 2 position screw terminal.

They are all mounted to a small acrylic sheet with double sided foam tape.

The acrylic sheet is then attached to the side of the power supply using 2 thin strips for easy removal.


This pretty much covers most of the power supplies I have used on my various CNC machines.