Laser Wiring - Duet 2 wifi - Duex 5
-
I've read a few posts in the forum and looked through the user manual and I'm still a little confused at how to properly setup a laser for engraving. I have a 24V PSU powering both the Duet 2 and Duex 5 board but my laser is 12V. The laser has three inputs (12V+, GND, PWM). Can the laser be directly powered from the Duex 5 board at 12V and if so can you please confirm which pins I can use as well as everything that needs to be included in the config to add the laser?
This is what I have in the config so far from the manual:
M452 C"exp.heater6" R255 F200 ; Enable Laser mode, on exp.heater3, with max intensity being 255, and a PWM frequency of 200Here is the laser I am using:
https://www.amazon.com/OXlasers-Focusable-Engraving-Module-3018pro/dp/B08DXRY424 -
I'm in a similar boat, though I don't have the Duex5.
The PWM on the Duet triggers the negative, so you can sort of use it. You can power the laser from the heater circuit, or at least the trigger. You can use a separate 12V supply for the positive side, and use the PWM management for the negative, or you can use something like this circuit to switch the PWM input from the laser, with a separate 12V supply. (I just got a few boards made for that circuit, which can be (apparently) plugged into the expansion header on the Duet2.)
Looks like if you want a native PWM manager, you need the Duet 3.
For the 12V version, you may need an external MOSFET, you just feed the 12V from a separate supply, tie the ground together with your 24V supply, and supply the ground through the MOSFET to the laser. The laser then stays at 100% and the heater circuit will manage PWM. It should work OK, but the fan will also be PWM controlled to match the laser.
-
@supraguy
In your Duet 2 example (without the custom board) nothing is hooked up to the laser PWM pin is that correct? -
@code7 It will somewhat depend on your laser, it might need a 3V3 connection (100% PWM) or it might have an "on" button on it, so it only needs the 12V connection.
I went ahead and ordered the PWM modules that will output the 5V PWM from the Heater 3 pin. Turns out that I got 15 of them because minimum orders, so depending on where you are in the world, I could probably mail you one for pretty cheap. (I didn't get the wire headers for the 12V/GND in, and the 12V/GND/PWM out because they didn't seem to be in stock anywhere.) I don't like using the PWM on the full 12V, but some people have had good results from that.
-
@supraguy
I'm interested in buying some boards from you. Thanks
