Hi
I have a problem I can not solve for hours now. Please help…
I’ve set up grbl on arduino to run my laser on my DIY-CNC. As you will see on the pictures, before I hook up my laser for real, I wanted to check the output signal on my oscilloscope.
I drew a simple circle in lightburn, set the laser power to 100% and wanted to check the signal coming out on the laser pwm pin.
The result is, at 100% power I get only 13%-14% duty cycle instead of 99%-100% duty cycle that would run the laser at full power…
$30 is set to 1000 to match lightburn settings and $32 is set to 1 for laser…
Please help !!!
EDIT : Just found out that not everything is wrong… When I set the laser to 20% for test firing it works correctly at 20% duty cycle …
Thank you for your fast answer !!
I’ve set the speed to 200mm/sec because I’ve used that speed and setting on my cnc while running the laser with mach3 and cutting at 100% ok…
I’ll run the speed right now at 25% (50mm/sec) and check… I’ll come right back…
Wow… OK… the speed really had an effect on the duty cycle !! When I reduced the speed 50% (from 200mm/sec to 100mm/sec) the duty cycle doubled up to around 28%-30%. When I reduced it to 25% (50mm/sec) I came to 55%-70%.
To be honest, I was thinking that if you increase the travel speed, the power should increase to compensate the lower “burn-time” (meaning the lesser power impacting one spot).
