hi everyone, need soe help setting up my laser tree 80w ProAA 12v diode laser, when ever i connect power it looks like im getting a constant 1.6v from my PWM, should this be 0 at startup? is this something i need to change in GRBL settings?
$$ $0=10 $1=255 $2=4 $3=5 $4=1 $5=0 $6=0 $10=1 $11=0.020 $12=0.002 $13=0 $20=0 $21=1 $22=1 $23=1 $24=850.000 $25=1500.000 $26=250 $27=5.000 $30=1000 $31=0 $32=1 $100=201.480 $101=200.340 $102=199.100 $110=2500.000 $111=2500.000 $112=500.000 $120=500.000 $121=500.000 $122=150.000 $130=660.000 $131=1300.000 $132=75.000 ok
the controller will turn off the PWM output when it gets a M5 command when it gets M3 S0 it is also essentially off M3 S1000 will output a constant 5v (or10v from the 10v pin - adjustable). (I see the web page says it is a TTL module, so do not connect the 10v output from the BB to the laser, ever, TTL is 5v by definition) M3 S500 will output a pulse stream that is 50% on and 50% off. But bear in mind that voltmeters do not read PWM signals well at all. They are designed for either plain DC, or AC sine waves at 50 or 60hz, PWM can be 1000hz or more, and square wave, not what the meter is expecting at all, making the readings suspect. so, when the laser is NOT connected, do you see 0 for off and 5v/10v for fully on at the blackbox terminals? does it change when the laser is connected? does the lasers user manual mention any pulldown or pullup resistors?
I see the manual says 3-12v on the PWM, which means it has an optocoupler on the input, and THAT will have a bias resistor which may be giving you a voltage offset. But it will hinge on the actual PWM output that the last M3 Sxxxx command demanded, so we need to know that actual state of the controller.
the manual says it accepts PWM as 3-12v this means it has an optocoupler on the input, which may be biased by a pullup resistor. I see on the adapter board there is item 10, the PWM indicator. that also implies some sort of bias resistor. both of those resistors will result in some voltage coming from the laser. note that the BB 10v output is NOT PWM, so you cannot use that on your laser. so, it remains to check what comes out of the BB when the laser is not connected.
hi thanks for your help, I’ve just checked and i’m getting the same voltage without the laser connected from the PWM pin.
then there may be something wrong with the BB itself, time to contact the store who will help you diagnose the hardware
If you power up the laser, and measure the wires you had plugged into the PWM port, what is the voltage on there? (not BlackBox side, but Laser side)
