Laser co2 50w+ grbl-lpc problem

hi forum, I built a laser with psu 50w + tube 50w, I loaded grbl-lpc (c.prezzi

) on mks sbase, I connected L hotbed less, it does not work well, I have at maximum power 9 ma, the tube and psu they work well, I attach my psu connector and schematic

Do you have a potentiometer connected to G/IN/5V?

no without potentiometer

Do you have a jumper wire installed which connects IN to 5V?

With these odd controllers which only use L for on/off and power, you either need a jumper wire to set the max to 100% of what the PSU can deliver or a potentiometer which acts as a limiter.

The max current of the PSU is usually higher than what the tube was rated for. Limiting the current in software or with a trimpot is definitely a good idea.

without jumper between 5v and in maximum power 8 but, with the jumper now maximum power we are 12 but, why don’t I get 20 but?

Where/how are you measuring current?
What else is connected to the LPS other than mains?

i connected analog ammeter, this psu does not have 24 v, i had to put an external power supply 12 v 5 a for the mks sbase, then i connected the gnd in common

i loaded smoothieware firmware, fire test from psu 18 ma, ligthburn 100% power 15 ma, it can also be the tube 50w vevor under dimensioned

I tried 2 different schemes with logic converter, scheme n 1 max 8 but, scheme n 2 max 20 but but when you move the laser in the passages it stays on 2/3% and it ruins the cut pieces

I would recommend this configuration:

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donkjr I use lightburn, I made a diagram with a 5v + in jumper, the maximum power reaches 20 but, but in the movements it does not turn off the laser, if I put a potentiometer I solve the problem?

The potentiometer will not solve that problem.
I think your PWM signal is inverted.

donkjr when i first did scheme n 3 with grbl -lpc the laser turned off I change direction, but lose steps, so i decided to put smoothieware and i solved lost steps, and started making this defect that stays on low power laser change direction, is there a solution?

If you use smoothie ware you can invert the PWM in the configuration file.
Then the configuration I gave you should work.
I use this configuration with smoothieware + Lightburn in my K40.

on the k40 with 40w it is easier, it is this psu 50w that gives me problems, what would be the configuration that I have to reverse on smoothieware?

Laser module configuration

laser_module_enable true # Whether to activate the laser module at all. All configuration is
# ignored if false.
laser_module_pin 2.5 # this pin will be PWMed to control the laser. Only P2.0 - P2.5, P1.18, P1.20, P1.21, P1.23, P1.24, P1.26, P3.25, P3.26
# can be used since laser requires hardware PWM
laser_module_maximum_power 1.0 # this is the maximum duty cycle that will be applied to the laser
laser_module_minimum_power 0.0 # This is a value just below the minimum duty cycle that keeps the laser
# active without actually burning.
laser_module_default_power 0.3 # This is the default laser power that will be used for cuts if a power has not been specified. The value is a scale between
# the maximum and minimum power levels specified above
laser_module_pwm_period 150 # this sets the pwm frequency as the period in microseconds

switch.laserfire.enable true #

switch.laserfire.output_pin 1.22!^ # connect to laser PSU fire (!^ if to active low, !v if to active high)

switch.laserfire.output_type digital #

switch.laserfire.input_on_command M3 # fire laser

switch.laserfire.input_off_command M5 # laser off

The type of laser power supply (40 vs 50) should not have any bearing on this problem. The control from the controller is the same.

I am not near my machine to check your config.
If I recall correctly the default smoothie config setting on the port has the correct PWM setting, i.e. does not need to be inverted.
In the meantime here is my config file for the laser. Ignore the switch commands

donkjr pin 2.4 is not pwm, why did you put switch.laserfire.output_pin 2.5 ^? this pin is hot bed less
send me your configuration to try it out

I just wanted to show you inversion/not inversion on a PWM pin.
You will need to configure for whatever pin you are using for PWM [2.5?] for whatever direction you want the PWM Signal? The LPS-L pin wants a ground true (turns on) signal

laser_module_pin 2.5 in your case looks like it should work.

Doe this mean that it runs a job but the laser stays on after and before a job is run???

with the n2 + smoothiware scheme I do not lose steps and arrive at maximum power 20 ma, but when you move the laser does not turn off it remains lit 2/3 but, the n3 scheme with jumper 5v + in, I arrive at maximum power 15 ma and the laser turns off when you move

I believe N3 is the correct configuration.

What does the LPS current read if you press the test button on the LPS?