# S-value max in Lightburn

Laser 20w, \$30= 1000 in lightburn S-value max=2000, laser works perfectly with adequate power. If I set the same laser to S-value max=1000, it works as if it were 10w!?!? Thanks

How are you determining this?

Itâ€™s likely with that setting that any power level over 50% is resulting in full power at all times.

Try a test. Enable â€śConstant Power Modeâ€ť in cut settings and compare 50% power at 2000 S Value Max vs 100% power at 1000 with a simple design. Do not run long at that power due to risk of overheating.

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I have two lasers. one module is 10w and the other 22w. When I set the speed to 1000 and the power to 80%, three passes. The same results are for the 10w laser and the 22w laser if the S-value max is 1000. When I set the speed to 100/80% and the S-value max 2000 for the 20w laser, then 2 passes are required. When engraving wood, speed 8000/19%, both lasers have the same engraving. logically, a 22w laser would need less power compared to a 10w laser

Youâ€™re mixing variables.

Is the real question why are you not getting the results you expect from a 20W laser?

Or are you asking about how S Value Max should be working?

Unless you have a fundamental hardware issue, going to 2000 for S Value Max when \$30 is set to 1000 will not have the effect of doubling your power. It will serve to make all power levels 50% or higher to be the max power.

You can measure this if you have a voltmeter. Test PWM voltage from the controller. For an Ortur machine youâ€™ll get ~5V for any power setting 50% or higher.

I also suggest you run the test I described previously using Constant Power Mode. That will eliminate any power modulation as a variable in the test.

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Thank you

Lightburn-Device setings-S-value max 2000, \$30=1000

Not following what youâ€™re trying to say here. Can you elaborate?

You need to compare the 50% power at S Value Max of 2000 with 100% of S Value Max of 1000. I think youâ€™ll find that the cuts are the same.

Make sure to enable Constant Power Mode.

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