China Laser Aux Trigger Output K40 M2Nano Board

I wanted to add air assist to my China k40 type laser machine. I didn't want to buy an air pump, and I didn't want to have my shop air compressor running all the time dumping air out of the nozzle when it was not running/cutting.

So I set out to find a "trigger" on the main board, to enable an air solenoid. The broad I have in my machine is made by Lihuiyu Studio Labs. Its called the M2Nano. I went to their site to find a pinout of the board. But it was all in Chinese. So will a little editing in Illustrator and Google Translator... I figured it out! I have added it here so everyone can see it.

Turns out the that this board, Ver. 7 has a 5DVC trigger output! Now this is my second China laser, the other has a a Ver. 5 M2Nano board, and it DOES NOT have these connections. So your mileage may vary.

Step 1:

I made this with 100% parts I had laying around. So your results may vary.

I had a 5VDC relay. So I thought I would just hook it up directly to the + & - connector on the board. No joy! It didn't have the capability to powering the coil in the relay. I needed to add a NPN transistor to trigger the relay, and use 5VDC from the laser power supply to power the relay.

I went with the 5VDC because the PSU already outputs 5V, so it seems the easiest way.

The relay, in NO mode, is used to switch a separate 12VDC PCU (wall wort) to power the air solenoid. Since there is no 12VDC output on the laser PSU, this was the easiest way.

It works like a champ!! When the laser starts to cut/engrave, the relay is enabled, and air starts to flow. Once the laser is finished cutting/engraving, the board has a 15 second dwell time before the relay is disabled.

This output can be used to do a lot of other things too... turn on water pump, exhaust fans and more. It can be easily configures to switch a 110v device.

Thank for looking. :)



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9 Discussions


Question 7 weeks ago on Introduction

This is an excellent tutorial, thank you. I've got one query please. Does the nano output a constant signal when the laser is working, so a non-latching relay is used, or does it work with a latching relay? Thank you in advance!

1 answer

Reply 7 weeks ago

I have moved on to bigger and better laser machines now. But if I recall, it is on while cutting. So use non-latching relay.


1 year ago

*** M2 Nano - Missing wire ***

Please help

I was cleaning my laser and dislodged a wire.

It still seems to work, but there is a wire loose now

* I am also a bit confused how there is only 1 wire (L) between the m2 nano mainboard and the laser power supply? and that the 5v wire on the mainboard is not connected, my older laser had 4 wires to the mainboard?

missing wire.jpg

2 years ago

Thanks for the information. You are the only person I can find on the Internet who knows anything about these controllers.

I have an 80W Chinese laser cutter that I'm pretty sure has a dead M2 Nano. I accidentally knocked the USB connector, which broke a pin. I've replaced the connector, but it says "Laser is disconnected" I see that there is a component "WR1" connected across the inputs and to ground. The plastic has come away from the die, so I'm assuming that it's been through some sort of overload event, and has cooked the CH341A USB interface chip, which seems to be unobtainable from anyone around here. I've ordered another board from China, but I'm wondering whether it is tied to the dongle somehow. Do you know. Maybe I should have ordered a board and a dongle. My assumption is that the dongle just controls access to Corel Laser. Do you know? Thanks in anticipation!



1 reply

Reply 1 year ago

From what i know the dongle is just to unable the system to work, kind of safety mechanism ( same idea was(or still is) used with professional kitchen design software 20/20 where you need physical element connected to a machine to make the software work - and limit the number of copies in use ) With the Corel Laser - Plug In used to power my machine you should enter into the software the Board Id# printed on board to make it work. The Lihuiu company have description of pin# of each port on their Chinese manuals. You can open it in Adobe Acrobat copy the Chinese letters and paste in Google translate and it is going do basic translation for this. I am using Publisher where I pasted images of the pages of the manual and I am putting the translations on the placeholders covering original Chinese text> In my situation my main concern is the port 6 (power port) which is different on M and M2 board. Since M board is nowhere to find i am trying to figure out differences to be able to use M2. Besides since I need to cut for now only 100# cover paper I am thinking about the diode based cutters with smaller 2 / 5 / 15W power you can find on Amazon. I am stopped with launching of my new line of paper products ( pop-ups) because I depend on single cutter. It can not happen again.


1 year ago


I have exactly same situation with the USB. Actually Seeing how it sticks out of the machine I protected it installing sticking out Electric Box cover but it happened anyway. I was trying to solder the USB back but I think i overheated the board and lost connection to one pin. So I am right now in same situation like you but my machine has the M board with 6 pins instead of 4 in power connection so I am searching for electric diagram and other info how to connect it. From what I see you can use the Dongle you have already. You can buy the M2 nano board on Ebay (from Chinese Seller) and pay with PayPal ( Be aware that paypal looks good only to moment when you have a problem - I bough some time ago some stuff completely not matching the description / opened dispute through pay pal and when the manufacturer returned the money In PayPal judgment I should pay it anyway- my guess whoever works there is under influence or do not bother to read the correspondence)

It is very tempting to toss the Chinese "machine" away and buy something better but you never know if you are going end up with same crappy Quality laser. The Good side of The Chinese Laser is that they follow some common sense when comes to cutting area sizes. None of American Manufactures is doing that.


2 years ago

i have version 9 of this board but I see you have the same tl+- connector for laser power. Have you sorted out how to control laser power via software so a user can cut and engrave in the same operations and do greyscale work. The laser psu has tl hi/low on it as well with the to low only being connected.


3 years ago

You don't know how much I appreciate this. Trying to do mods to my K40 but obviously everything is in Chinese so...