I have finally got a chance to replace my old xPro V3 with a brand new V4 w/Spak Concepts box. The board pretty much works right out of the box with exception of setting laser mode(I'm using Acro laser), size dimensions and steps/mm. After fine tuning the steps, I let it cut its first job. after 20 minutes or so, I noticed that the stepper motors were running super hot. Before upgrading, with V3, the motors would be lukewarm even after running for 10 hours. Any ideas? Here's my setup: ACRO laser 510 5W laser NEMA 17's 24V LRS-350-24 power supply Grbl 1.1g by openbuilds specifically for Acro lasers $0=10 ;Step pulse time, microseconds $1=255 ;Step idle delay, milliseconds $2=0 ;Step pulse invert, mask $3=6 ;Step direction invert, mask $4=1 ;Invert step enable pin, boolean $5=0 ;Invert limit pins, boolean $6=0 ;Invert probe pin, boolean $10=0 ;Status report options, mask $11=0.020 ;Junction deviation, millimeters $12=0.002 ;Arc tolerance, millimeters $13=0 ;Report in inches, boolean $20=0 ;Soft limits enable, boolean $21=0 ;Hard limits enable, boolean $22=0 ;Homing cycle enable, boolean $23=0 ;Homing direction invert, mask $24=2000.000 ;Homing locate feed rate, mm/min $25=1000.000 ;Homing search seek rate, mm/min $26=250 ;Homing switch debounce delay, milliseconds $27=1.000 ;Homing switch pull-off distance, millimeters $30=1000 ;Maximum spindle speed, RPM $31=0 ;Minimum spindle speed, RPM $32=1 ;Laser-mode enable, boolean $100=57.472 ;X-axis steps per millimeter $101=57.203 ;Y-axis steps per millimeter $102=199.100 ;Z-axis steps per millimeter $110=5000.000 ;X-axis maximum rate, mm/min $111=5000.000 ;Y-axis maximum rate, mm/min $112=2500.000 ;Z-axis maximum rate, mm/min $120=2000.000 ;X-axis acceleration, mm/sec^2 $121=2000.000 ;Y-axis acceleration, mm/sec^2 $122=50.000 ;Z-axis acceleration, mm/sec^2 $130=960.000 ;X-axis maximum travel, millimeters $131=344.000 ;Y-axis maximum travel, millimeters $132=68.000 ;Z-axis maximum travel, millimeters
I've tried checking voltage on A1-A2 and B1-B2: They are showing 24V and no matter how much I turn the voltage adjuster, it still shows 24.
Hi Steve, the pot adjustment changes the current not the voltage, just turn them down until you can do a run without getting to hot. Gary
Gary, Thank you for the pointer but I am still wondering if there is a way to do this type of stuff in a methodical fashion. Isn't there a max amperage a motor can take, shouldn't there be a way to find out what it is and how to adjust the board to match it? In the mean time I turned the pots down to the middle and the motors are running fine now. Still I'm hoping someone can give an answer or point me to the information.
Pololu gives a pretty good explanation on how to tune 8825 drivers. You might give it a read. It may be possible to pull a Vref between the center pin on the potentiometer and a ground. (Then again it may not so if you attempt it you do it at your own risk.) The explanation and video can be found half the way down the page here.
Rick, these are not plug-in type of drivers: they're soldered on the board. while I'm familiar with setting up pololu style drivers I've never hard to deal with the on-board ones. Is there a diagram with pin-outs for the board I can reference?
