Hello, other than the S value max, is anyone able to explain these other settings that are in the machine settings tab?
The GRBL doc may be helpful, starting with $30:
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Some of these values are not really common to older grbl machines. Likely why the links don’t show the value.
I’ve run into them a few times and I’ll try to explain what they do. Most of them are available with a dsp unit like the Ruida and I’ll use their operation as a reference.
Maximum/minimum spindle speed ($31 and $30). These are generic control boards, the spindle speed is communicated this way. These used to be 8 bit values so the range was limited but in a nut shell… Most of the 8 bit controllers used this 256 value method, however when the controllers allowed a 16 bit value, a larger range gives you finer control.
I’ve yet to see a good grayscale that is a complete 256 steps from white to dark. Can’t imagine adding finer control does anything for you, but that’s just my opinion.
If min/max is 0 and 1000, then at 50% power, an S500 code is created. If it’s 0 and 256, then an S127 value is generated. Both the software and the controller have to know these pair of values.
The $32 was added for laser support. On a spindle you don’t need to slow it down to change it’s position, just lift it up, move and lower it. With a laser you want it to turn off when it move over areas that are not to be lased.
PWM Frequency, the correct term is period, although they are related. PWM is not frequency related, hence the term period. Some people call this a pwm base frequency, but it’s how fast the pwm is encoded.
A 1kHz pwm frequency is really termed as a 1mS period. – 1S/1000 = 1mS
If your gui is correct, I can’t figure out much use for a pwm frequency of 1 Hz.
PWM off value isn’t use on the Ruida, but I’ve seen it used on some DLC32. Seems to have had or still has a bug as this is only required in one machine with one type of firmware. I probably don’t know all of it’s uses, never looked at the code.
The Min/Max pwm values are in a Ruida, these limit the users software control to be within these two.
Make sense?
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Thanks for the reply, Yes parts of it make sense as I am not fully knowledgable of Ruida controlers either.
What I am attempting to understand and create is I have a CO2 laser that I can not get to fire and engrave at a lower power. Many materials engrave to deep and through. Even at a speed of 10000mm/m and 0.5% power using Lightburn.
I have not changed any of these values shown as is i do not fully undersand what they are. I am assuming Spindle speed relates to min and max power to laser.
Is it engraving too deep? Even with these supplied settings?
Most glass tube lasers will not lase below about 10%, each tube is different.
Does your machine have a mA meter so you can tell what kind of current it’s drawing?
Most controllers have similar settings as they are a generic contoller that will work on a bunch of different machines.
Do you know if the PWM control is sent to IN or H of the lps?
Do you have a connections schematic so I can see how you’re wired up to the lps?
Yes. it is engraving to deep and burning through with the settings above. As many jobs I would like to go slower for accuracy but then it burns deeper. This is only a 40Watt CO2 machine. I changed the control board to a monport so that it would accept Lightburn.
It took me about 1 year to get it properly wird so it would work almost satisfactorly. This is what it is today.
I think you have a goof at the wiring of the L terminal. I suspect the fire button is supposed to be across the L and G (or WP) and one side of the laser enable switch should go to L. L needs to go low for it to lase.
I suspect you can just parallel the two switches, so either pulls L low (wired OR).
Unless you want to stand there holding down the push button, it shouldn’t work.
These are usually wired with the controllers pwm wired to the IN terminal.
I suggest you change your speeds to mm/s and not mm/m… I use mm/s for everything, but they usually recommend mm/s for co2 machines.
10000mm/m is ~166mm/s and it should mark that, but I don’t know if you’re actually lasing at that point.
Do you or the lps have a mA meter? If so what kind of mA are you reading?
@jkwilborn thanks again for replying. would you be able to do up a drawing of what you concider should be correct please. State changed from what I have in the drawing.
Also when I am engravie at .5% the ma meter is about 2.5-3ma
Does the Monport support the GRBL $$ command?
Sorry… As we discussed previously, use L for enable and IN for pwm current control.
The controller has no convenient way to pulse the laser.