Nema 23 with expansion breakout board and external driver
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Hello guys
we have installed the duet with an expansion breakout board to drive a NEMA 23 motor with an external driver for z-axis.
After we installed everything and made the setup with a computer, the x- and y- axis of our printer with NEMA 17 motors work great.The z-axis with the NEMA 23 is moving, but not in the way it should.
For example:- Home command: it drives a few centimeters and stops way before hitting the endstop
- Z+100 command: it drives a centimeter gets slower, drives a centimeter, stops and then repeat it.
The jumper settings are set as they were delivered. (Green one is placed, Yellow one not)
We added a pic of the jumper setting, the external motor driver characteristic and the programmed file.
Maybe someone has a solution for us. Is it possible that the motor only gets 3.3 V instead of 5V?
Thank you!
12_1547539344573_tpre0.g 11_1547539344573_tpost0.g 10_1547539344573_tfree0.g 9_1547539344573_stop.g 8_1547539344573_sleep.g 7_1547539344573_resume.g 6_1547539344572_pause.g 5_1547539344572_homez.g 4_1547539344572_homey.g 3_1547539344572_homex.g 2_1547539344572_homeall.g 1_1547539344571_config.g 0_1547539344562_bed.g -
Did you extend the step pulse timing to meet the requirements of your external driver, using the T parameter of the M569 command?
The Duet WiFi/Ethernet will drive Nema 23 motors directly if you choose them carefully.
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The step pulse timing should be right.
The Nema 23 motor we have, needs the breakout board.
We have measured 3.3V on the Enable (ENA) contacts from the driver. How do we get 5V there, as needed? -
@robinfaurecia said in Nema 23 with expansion breakout board and external driver:
The step pulse timing should be right.
No, it isn't. Your config.g file doesn't have any M569 command for the external driver. Your M584 command says you are using driver 5 for Z and the information you quoted says you need at least 2.5us step pulse width, 2.5us step pulse interval, and 5us direction setup time. So you need to add this command:
M569 P5 S1 T2.5:2.5:5:0
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It works now Pretty good.
Another Thing is the homing Speed:
we can't find a way to Speed it up. It drives very very slow in z-axis.
Any Solutions?Thanks!
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There is also another Problem.
The steps/mm amount at the Z-axis is not working correctly.It is a 3mm Trapezoidal Thread. The Driver is set up to 6400 Steps/rev.
This means steps/mm is 2133.3Actually we Need 21333.3 to get it working properly. Where is the mistake?
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@robinfaurecia said in Nema 23 with expansion breakout board and external driver:
It works now Pretty good.
Another Thing is the homing Speed:
we can't find a way to Speed it up. It drives very very slow in z-axis.
Any Solutions?Thanks!
The homing feed rate (speed) is in your homing file(s). Adjust the F value in the line for the appropriate axis you want to move quicker.
Seeing your second post, you need to get your steps per mm correct before changing any feed rates.
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@timcurtis67
Do you have any ideas About the Problem with the steps/mm? -
@robinfaurecia said in Nema 23 with expansion breakout board and external driver:
@timcurtis67
Do you have any ideas About the Problem with the steps/mm?Are you sure that your motor doesn't include a 1:10 gearbox?
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Yes absolutely.
The Variation is not exactly 1:10. It varies with every move.
I think there is still a problem with the step/pulse timings. Although we met the driver requirements.
Any ideas?