In lightburn, is it possible to scale power for DSP in the same way as for GCODE (S-value)?
I bought a 60W CO2 laser and in it the maximum current (22mA) is already generated at 59% of Lightburn power and the minimum power of 8% at which the laser beam lights up.
I would like to scale Lightburn’s DSP control so that lightburn’s 100% would actually give only 59% power. That is, the same as if I changed the S-Value of GCODE from 1000 > 590.
Is this possible in Lightburn?
I have set the power limitation in the Ruida controller so that it does not exceed 22mA with any setting.
Are you sure that you can limit the max power output through the Ruida controller?
As far as I know, it is only possible by limiting the output of the tube’s power supply itself.
I’m sure and tested it with a mA meter before and after changing the setting. I have a Ruida 6445 controller, and in its Vendor settings it is possible to limit the maximum and minimum power output to the tube. I made the settings changes via Lightburn Machine settings.
Yes you can, but not like the grbl based machine … why would you want to?
On an dpssl it lases at 100% no matter the percentage you set. It’s power/time on these.
As you’ll see, I think you’re going at it from the wrong angle.
I think what you want is 100% power in Lightburn, causes the machine to lase at 22mA. ?
Because that’s what I would want …
No brain exercises. If you want 50% of your power you enter 50% in Lightburn.
This limits the range of the pwm generated signal. If your machine lases at 10% and you set that as minimum, then setting the maximum of 50% allows pwm control only over a range of <40% of what it should be.
You should have pwm adjustments from 10 to 100% (99% in the Ruida) or 90% variability. That is over twice the control you would have limiting the range within the Ruida.
Keep in mind that when a glass tube lases, it will draw as much current as the lps will supply.
The suggested procedure on a co2, is to set the current/wattage limit within the lps to the maximum of your choice, current or wattage.
This will sync 100% power in Lightburn with whatever you have set within the lps.
If you wish to do this, I can give you an easy and safe procedure.
The concept is pretty simple. You set the lps internally for your maximum current or wattage when the signal to it (pwm or percentage power) is 100%.
In order to ensure you don’t allow too much current during the setup, I set the pwm to 50% and adjust the internal current control to 50% or 1/2 the desired current or wattage.
This is a rather standard conservative approach to avoid damage when doing these kinds of setups or adjustments.
Generally these produce too much current so setting it to 50% makes it certain you won’t be working in a dangerous current level for your tube.
Tubes are not linear, but are reasonably close.
The maximum current, doesn’t necessarily mean your output power is at it peak. Many people check power output and current levels in increments. Most find that the output wattage will peak before you reach tubes maximum current rating.
Once output power is at it’s peak, there is no advantage to increasing the current to the tubes limit.
Configure the Ruida to pulse continuously at 50% power. This allows you to hold the pulse long enough to get a stable mA meter reading.
The lps should have a hole in it to access a 20 turn pot for this adjustment. On the ones I’ve adjusted, rotation to the right increases current. I have a set of ceramic screwdrivers, but many use regular screw drivers that can conduct…
On my machine it helps to be a contortionist because of the adjustment location.
I have mine set to it’s maximum, but I’m going to check output wattage/mA and probably readjust for 100% power = 100% watts out instead of 100% power = 100% tube current…
I can’t find where the settings you advised can be found in my machine’s console. I have a Ruida 6585 as a panel, which controls a Ruida 6445 controller.
I’ve only owned a CO2 laser for less than a week, of course before that I used the Ortur LM3 10W diode laser, so I’m still learning how to use the new device.
After using LightBurn to update the Vendor settings did you reset the controller? You may need to reset the controller for the new setting to take effect (press the ‘Reset’ button on the control panel).
What value did you set in the machine settings for ‘Laser 1 maximum power (%)’?
After resetting the controller go back into Vendor settings and check if the update was written successfully.
I say this because on my Ruida controller (RDC6442G with firmware v8.07.70), once I have set Min and Max power % all power values from LightBurn are scaled so that 0 to 100% from LightBurn will translate to expected values between Min and Max power % for the PWM signal to the power supply for the tube as observed and detailed here.
So at least in my case, it is not necessary to also trim the power supply.
