Problems conect to Cohesion3D

Hello! I need help I have this target i Want to conect the Cohesion3D where do I should the conection I have? (the numbers) The number 1 I know conect it but the second and third… ? thanks!

This is a bit uncommon. I have a feeling I know what’s going on here, but I’m going to need a couple more pictures, most specifically of how things connect to your laser power supply, to know for sure.

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They tell me that I spam the images. I have a stupid face. And as a new user they won’t let me upload images.

Are these images useful?

I have managed to connect the Cohesion3D card with the software. The problem is that the Y axis is reversed and I don’t know where to connect the two wire connector. I think that’s why I don’t have laser power.

Hi Dafne,

Please post new pictures of the new board and wiring so we can help you troubleshoot further. Thanks for your patience while we reviewed the details.

The wires in the 2 pin cable (TL / LO and Gnd) located at the top right will need to be connected to the screw terminals on the C3D, which are the Laser Fire and Laser Gnd respectively. You can ignore the 24V and GND 4 pin connector since LaserBoard has its own power supply for the board.


This page covering the 6 Pin Laser Power Connector will show where to connect them at the bottom of the link.

First, check that your origin is set properly in LightBurn and that the bed sizes match in Edit > Device Settings. More information: Origin Setup

If your machine homes to a different location than rear left or moves opposite of what you expect, check your Y connector to see if it is inserted into the proper header and is in the correct orientation (not reversed). We need to see pictures of your current board and wiring to help troubleshoot further.

Alternatively, you can invert the direction pins on the config file by removing or appending an exclamation point for the following options: alpha_dir_pin 0.5! and beta_dir_pin 0.11!

In LightBurn, on the “Move” tab, test the jogging using the arrow buttons to confirm:

  • Left arrow moves left
  • Right arrow moves right
  • Up arrow moves toward the back of the machine
  • Down arrow moves toward the front of the machine

Report back with the results, please.

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Now it moves well. Change the pin!

  • Left arrow moves left
  • Right arrow moves right
  • Up arrow moves up
  • Down arrow moves Down

And now it burns.

The power in the machine should be set to 99.9 and control the output from the Lightburn program?
Accustomed to the% of the other card now I mess up a bit with Lightburn. Before to cut I put it at 22 power, but now it is less, 10 or less.
Is there a table of engraving and cutting powers to give me an idea of ​​how to work?

By the way, thank you very much for the great help you have given me.

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Hi Dafne,

I’m happy to hear you the machine firing and the motion running properly! The large white power plug is not necessary to have plugged in with this wiring configuration.


The power can be controlled from the laser, as well as from LightBurn speed and power settings.

Depending on your machine setup, the power is adjusted on the control panel using a potentiometer or digital keys. For the pot type, you would set the knob to your maximum limit (usually 15 mA for a 40W tube) and adjust the power via LightBurn. Here is a recent post that you may find helpful regarding setting power on the laser:

If you do not have an mA meter, we recommend getting one so you know what your power your laser is actually outputting and don’t overdrive the tube. I can help with wiring instructions, if needed. I would need to see pics of your machine and control panel.

This article explains how to adjust and test your PWM levels for the machine:

Do some practice runs to determine what combinations perform best on your machine, such as a ramp test to determine your focal point for cutting or engraving, and a power scale test to determine what settings give you the best engraving output.

One other note: The blue USB cable is known to cause communication issues and should be replaced. We recommend using a data only, high quality, shielded USB cable.

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Thank you.

My laser is 60W .

I just bought the 30 mA ammeter and multiturn potentiometer which comes to me in a few days.

The USB cable I use is the one I bought here on this website to avoid problems.

This is the panel of my 60W machine outside and inside:

Hopefully you can help me connect the ammeter and not bother you anymore :yum: :yum:

Hi Dafne,

Thanks for your patience while we put together some documentation - I updated to include your type of power supply. For installation instructions: How to Connect an mA Meter

Let us know if you have any questions.

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Thanks for your answer. I already installed the ammeter.

And any guide on how to install the Multi-Turn+Potentiometer?
What I see is not very clear to me. I am somewhat clumsy with electronics.

Hi Dafne,

I’m glad to hear you got the ammeter installed.

Our potentiometer installation is covered at the bottom of our LPSU Connection Guide.

Let me know if you have any questions.

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