# Need some help, cant spec the pulse on a stepper

Its a 57bhp79-580-32
I just cant find the pulse rate on it
In a rotary attachment,
Busy doing the setup, just wired in the relay in on the y axis, nextstep will be the software side,
Any body here familiar with this motor?
Thanks.

It’s either going to be 200 or 300 steps per rev. Most likely 200. The driver controls the microsteps however.

Warning - I am not 100% confident that I actually know what i am talking about.

I think that is a 1.2º step angle 3 phase stepper motor originally designed for a labeling machine.

With that, 1.2º step angle 360 / 1.2 = 300 steps per revolution.

And just as Travis mentioned, your driver (which is also shared by your Y) is controlling the actual steps (pulses) per Revolution. Now consider that in Lightburn under the rotary settings you can adjust / translate the info sent to the driver to compensate for how many pulses should be output to achieve accurate linear movement. This is to account for things such as gear ratios from belts and pulleys.

If your Y axis is working properly, don’t mess with anything else other than the rotary setup. In other words, don’t adjust your stepper driver dip switches.

Also, this is what I have in my rotary (with a 1.8 degree step angle / 200 steps per rev):

To expand on what Jeff said…

If your motor is a 1.2 degree motor then it has 300 native steps per revolution. 300 * 1.2 degrees = 360 degrees.

Your motor driver has microstepping capability. There are usually dip switches and a chart to set that. So by example it could be set to 4 microsteps per native motor step in which case it would be 1200 steps per revolution. You’ve got to tell LB how many steps it takes to rotate the motor one revolution. It you were directly driving the rotary in my example it would be 1200. But you’ve got a timing belt in the equation. So you need to account for the number of teeth on each pulley and calculate the ratio. If the driving gear was 10 and the driven gear was 40 you’d have a 4:1 ratio and the answer would then be 4800 steps per rotation.

It’s native motor steps * microsteps * gear ratio.

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