M2Nano to LaserBoard and 40W to 50W LPSU

Machine: K40, M2Nano

Board: LaserBoard

Firmware: “I have a new board and I’m using whatever it came with”

Problem/ Question:

LaserBoard PSU
24V LED Back light
5V diod laser pointe
Digital Power Setting and Display

I am upgrading from the M2Nano for a LaserBoard and swaping in a 50W LPSU to replace the stock 40W.

Question 1: is the Blue Wire on the back of the LPSU the “L (Laser Fire)” wire? In my diagram I have it as “TL” but I think this may be incorrect.

Question 2: I want to keep the PowerPMW to set max power limit. But do not know where to connect the “P+” wire.

Question 3: I’m not using an inline flow detector (my water pump has its own LED indicator), so do I need to jumper the “WP” to the “G” on the LPSU?

Question 4: Should the “diod laser for centering” be wired to the LPSU, to the LaserBoard, or both?

Question 5: Can I wire the 24v LED Backlight to the LaserBoard without loss of performace from the X and Y motors?

Thank you for your time and attention.

I’ve attached images of the LPSU, Digital Display, and pinout chart

Is it too late to suggest that you do the upgrades one step at a time?

The C3D board default wiring is to send PWM via “Laser Fire” on the C3D to TL on your LPSU. Additionally connect “Laser Gnd” from the C3D to G on the LPSU.


Our default wiring also calls for something to set the max power on the LPSU, whether that is the digital panel or a potentiometer. This logic is explained in one of the articles on the Forum FAQ section.

While that sounds vaguely close to advice I have heard before, I cannot tell you for sure and you should seek confirmation from other resources or laser groups.

We recommend not powering any peripherals off the C3D Boards. You can pull 5v off the LPSU for the laser diode, but you’ll need a separate psu (I’d recommend a small wall wart) for your led strip (if it’s indeed a 24v, most I have seen are 12v, so check that).

This thread contains more details about the LPSU wiring: