PWM vs Analog

[wmgeorge]

My laser has a 35 watt tube about 800 mm long and the 40 watt PS has only 0-5 volt signal input for control. IS there an advantage to going with a new PS with PWM? I seem to have trouble in cutting but not engraving. The controller I have and the software both support PWM.

[Tech_Marco]

You need to measure the output current from the Laser power supply to the laser tube. For 800mm tube (40W), you may need 16~18mA to drive it. Less cutting power usually caused by aging tube or bad focus lens, assuming focus is fine tuned. PWM helps better on engraving. FYI cutting, it is not irrelevant though. FYI, 5V applied to the IN will drive the power supply in full power output.


Marco

[wmgeorge]

You need to measure the output current from the Laser power supply to the laser tube. For 800mm tube (40W), you may need 16~18mA to drive it. Less cutting power usually caused by aging tube or bad focus lens, assuming focus is fine tuned. PWM helps better on engraving. FYI cutting, it is not irrelevant though. FYI, 5V applied to the IN will drive the power supply in full power output.
Marco

Right now the MA meter is in series with L- on PS, a small black wire connected to it goes to meter and then onto terminal on - side of tube. It shows over 20 ma more like 22 or 24 when on 100% which I never run at. IF I thought it would not hurt my Fluke DVM I would hook up in series with that to read more accurately. The tube is marked 35 watt Certified and its on a 40 w PS. This is a G.Weike machine the Storm 500. I can not cut 6 mm acrylic only about 50% and 3 mm plywood about the same.

This is the controller CNC-LS240A by LeadCNC.
Willing to buy whatever I need from you but waiting until this tube fails and will upgrade to a better PS and tube.

[Tech_Marco]

You may be able to cut through 4mm acrylic with 1.5~2mm/s in speed. If that is the case, you're fine.
When I fine tuned a K40 (my customer machine), I could cut through 13mm without a problem with 1~1.5mm/s
Well, it all depends on the density of the wood, even though it is the same kind of wood.

Marco

[Tech_Marco]

Correction: I could cut through 9.5mm

See my post: viewtopic.php?f=70&t=1332


Marco