I am currently trying to run my K40 with Lightburn. The motors and sensors are working fine, but unfortunately not the laser. For some reason I have no output on the laser, I have connected L of the PSU to Spindle - and both GND of the MKS DLC32 and PSU. Unfortunately I don’t get any output, does anyone have a guess what the reason could be? Is there anything that needs to be set in Lightburn inital?
The lps (laser power supply or high voltage supply) has two basic control lines. This excludes the P input which is for coolant flow protection.
The IN pin, controls the lasers current limiting. This can be a pwm or a dc control voltage. On a K40, it’s commonly the pot or current control knob that sets the voltage.
The L input, which is active low or inverted H, is for enabling it to lase.
When L goes low the tube will lase and limit current relative to the control voltage on IN pin.
How are these wired on your machine?
The P input must be held to low (or to ground) to tell the lps that the tubes coolant is flowing… On my machine, the controller handles this, so it’s wired directly to ground.
These are the control signals you need to drive the lps. The pwm signal is generally applied to laser enable or the L input. These grbl boards do not have a laser enable…
There is nowhere you show how you are really wired… if you only have two wires to the lps, it’s probably not going to work properly.
I suggest you stay away from the spindle interface, it will put whatever the supply voltage you are using on that output…
Na it doesent work what i think is strange, the normal Voltage on the Spindel minus is 23 ish Volt, thats in my opinion fine, if i try to Laser something it just go down to 16 ish Volt i thougth it should go to 0
So if the MKS is not connected L to Spindle i have 0 Volts on L when P and G is shorted and 4V if its open, when i connect L to Spindle i have 16 V while a Laserjob an 23 when “Idle”
