k40 with digital control panel questions
Hello, all. I recently purchased the MG3 for my k40 after the stock M2 Nano died. The installation went fine, and I was able to do a basic test in Lightburn, but I have a few questions/issues post-installation. I searched the forums and found some answers that I think I understand, but verification would be nice.
- My panel also has interior light and main power switches. The light works as expected, but if the unit is plugged into mains, the laser starts constantly firing when I turn off the main power switch on the panel. I'm very concerned about this, but I'm not sure where to start looking. I have the power supply shown in the installation video, so I followed that exactly.
- If I understand the forum posts I've found, laser output power control has been taken over by the MG3, and the physical buttons can be removed or disconnected. This includes the display itself, the ±10, 1, and .1 controls, and the laser test fire button. The laser safety on/off switch still seems to work, so that can stay?
- Since the MG3 now controls everything, the "Power Max (%)" setting in Lightburn refers to the max output for the power supply and laser, not to whatever the display shows?
Thanks for any help.
My panel also has interior light and main power switches. The light works as expected, but if the unit is plugged into mains, the laser starts constantly firing when I turn off the main power switch on the panel. I'm very concerned about this, but I'm not sure where to start looking. I have the power supply shown in the installation video, so I followed that exactly.
Best is to measure if the LO and IN signals are working. Use a multimeter to check there levels. LO 0 volt means the laser is on. IN 5V means full strength. So maybe a cross wiring happened? Use a Ohm meter to see if there is continuity. A loose IN wire (disconnected of floating wire) has a pull up resistor on the power supply so automatically goes full blast. The terminal screw might not touch the bare copper wire... also check continuity between grbl controller terminals and power supply. Disconnect the grbl controller and measure if a wire is a continuous connection to ground.
If I understand the forum posts I've found, laser output power control has been taken over by the MG3, and the physical buttons can be removed or disconnected. This includes the display itself, the ±10, 1, and .1 controls, and the laser test fire button. The laser safety on/off switch still seems to work, so that can stay?
Yes the safety on/off push button can stay and is a safety measure.
Since the MG3 now controls everything, the "Power Max (%)" setting in Lightburn refers to the max output for the power supply and laser, not to whatever the display shows?
That's correct. Max Power which is gcode S= value. The reference value in LB or other G code senders is often 1000. So S=500 will send 50% power.