Diode laser connections

Machine: K40 laser . Installing a 30w blue diode laser with 4 wire pwm or 2 wire TTL connection

Board: cohesion3d

Firmware: _Smoothie

Problem/ Question: I am putting a diode laser on my K40 setup. Need to know how to connect to the cohesion3d board I have either a 4 wire pwm straight to laser mod or 2 wire TTL thru a pwm board. I also have the digital panel from the co2 laser . What the best way to hook this thing up.

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Hi Terry,

Do you have any specs, additional labeling, or markings written on the diode module? I took a look at the link on the visible label, but your model and control board looks different.

  • What type of connectors are used on your diode module? They are obscured in the photo. Can you take some at different angles where I can see any pin info and wiring, please?
  • What power supply (voltage) is included, if any?
  • What amperage is required to run your diode laser?

Once we have a little more information, we can give direction on wiring.

What I want to do is use my existing k40 gantry and setup but disconnect the co2 laser and mount the diode laser on the gantry I’ve tried the 2 pin pwm output and it works fine on cutting and power level seems to work. But if I disconnect co2 power from cohesion3d board nothing works . And if I try engraving I get no output. So basically I need to know how to set this all up. He are details and pictures.
Diode laser was purchased here



Sorry phone wanted to fight me uploading pics.
So do I skip the little board and go straight to laser. Hope so I power laser since it’s 12 and board supply is 24. I need to make sure co2 laser isn’t getting power .
And the engraving thing laser fires while cutting but not engraving. Thanks

Hi Terry,

The 2-pin connector is typically used for input signals “GND” and “PWM” on the diode.

This will connect to screw terminals on the LaserBoard, so the wires would need to be cut / stripped, or you can adapt with end connectors, depending on your comfort level.

For the 2-pin from the diode, the positive wire (typically red) will go to the + marked at the top left of the board, marked “Separate Power”. This is the orange wire in the image below.

The single negative wire (typically black) will go to the Laser Diode Out on the left side of the LaserBoard. This is the blue wire in the image below (the other dark line is just a shadow).

This resulting connections will appear as such:

You may also need to account for the added weight on the gantry and adjust the configuration accordingly, to ensure that the head can start and stop without issue. This may require upgrading to heftier stepper motors and external stepper drivers, but may require trial and error testing to get your settings dialed in properly.

You would only turn on one device at a time with a switch, whether that is a physical switch or a digital one that is controlled by the board and some macro buttons in LightBurn.

You may also find these posts helpful, including the corresponding links included:

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