Benbox Laser Machines/CO2 Lasers/3D Printers

General Category => Trouble Shooting => Topic started by: Tribo on October 05, 2020, 09:47:42 PM

Title: Connecting the laser directly to the source
Post by: Tribo on October 05, 2020, 09:47:42 PM
I use a 15W laser connected with this three-wire cable, where yellow is wpm ... everything works ok.
I decided to use the cable from the third photo, which came with the laser module, in this, the wpm wire (red) I call where the yellow was in the first photo, but the laser is always on at max ...
What am I doing wrong? it seemed to me a logical thing.


(https://iili.io/2ObCRR.md.jpg) (https://freeimage.host/i/2ObCRR)

(https://iili.io/2ObFKg.md.jpg) (https://freeimage.host/i/2ObFKg)

(https://iili.io/2ObBHv.md.jpg) (https://freeimage.host/i/2ObBHv)
Title: Re: Connecting the laser directly to the source
Post by: ggallant571 on October 05, 2020, 10:52:34 PM
The three wires are GND, +12V, PWM. Traditional colors are GND =BLACK, Power= RED. You need to match the the signal names, not the colors. Looks lie your second picture is designed to use an independent power supply. If your go that route to need to connect the GNDs.

With a 3-wire connection most laser modules use a high (> 2V) to signal ON. The controller firmware drives this signal LOW to turn the laser OFF. If that active drive signal is missing the input on the laser module will float high resulting in a steady ON condition. Many of us have installed pull-down resistors on the PWM line to avoid this condition. I typically use a 3.3K. Cost is about 0.02USD.
Title: Re: Connecting the laser directly to the source
Post by: Tribo on October 06, 2020, 07:21:07 PM
It's ok. I saw the GND connection in another post, I'll try.
Thank you.