some questions on high speed stepper stalls
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First post and wish i had found this forum a few months ago
They say stepper motor suppliers love newbies
I have a Warco wm18 mill and have added a power z axis stepper but it stalls at high speed
This is the driver i am using - https://www.oyostepper.com/goods-111-Digital-Stepper-Driver-10-42A-20-50VDC-for-Nema-17-23-24-Stepper-Motor.html
This is the stepper motor - https://www.oyostepper.com/goods-88-Nema-23-Stepper-Motor-Bipolar-3Nm-425ozin-42A-57x57x114mm-4-Wires-CNC-Stepper-Motor.html
This is the power supply -https://www.oyostepper.com/goods-375-150W-24V-65A-115230V-Switching-Power-Supply-Stepper-Motor-CNC-Router-Kits.html
I have set the driver to 4.2a and i think, can't remember without opening enclosure, to 1600 steps/rev
It works quite well but tends to stall at max speed especially raising the head. For info the head does have a gas strut helper
so where have i gone wrong?
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Stepper motors are not high speed devices. They have lots of torque at low speed but rapidly loose torque as speed increases. This is doubly true when you drive it with a relatively low voltage and you quickly loose power because of back emf.
I don't know what you consider 'high speed' but anything past a few hundred rpm is bound to cause issues.
You would need to limit maximum speed to stay within your required torque zone. -
OK, thanks for your reply.
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There is a motor EMF calculator at https://www.reprapfirmware.org/ that will estimate the speed at which the motor torque starts to drop off sharply. You can use that to work out the maximum speed you should use for that motor, given the PSU voltage and other parameters that you are using.
