Hello Guest it is May 22, 2019, 09:34:26 PM

Author Topic: stepper motor slow but still stalls  (Read 2596 times)

0 Members and 1 Guest are viewing this topic.

stepper motor slow but still stalls
« on: May 21, 2016, 10:23:29 AM »
I am new to CNC and need some help. In April, I bought a kit from Wantai motors which included a breakout board, cable, three DQ 542 MA drivers, three 57BYGH115–003B stepper motors and a 350W 36V power supply. I placed the motors on a Jet JMD 18 with a 4:1 gear reduction for X and Y axis and a 3:1 reduction for Z axis. My drivers are set on 2.84 A and 400 steps with switch 4 turned off. I've connected breakout pins 2-7 to the negative driver dir and pul terminals and also to the positive driver terminals with the same results. In Mach3, my port one address is 0X378. Breakout 2-7 are assigned to the correct step and driver pins with step and driver port set at 1. I've tried DirLowAct and StepLowAct both checked and unchecked. My Estop is checked with post 1 and pin 10 and active low selected. Digit trig is set at port 1 and pin 1 and is enabled.

The problem is that as I try to set the steps per unit I have had to lower my velocity to less than 1 and acceleration to 0.5 but my motors still stall and otherwise moves eratically. This especially happens when I change directions. I do have backlash values entered. I'm unable to consistently configure my steps per unit because I am moving an inconsistent distance. In its current state, I notice that when I briefly push the jog keys, the motors continue to run another 5+ seconds. I've tried multiple microsteps with the same results. I tried Sherline 1/2 pulse mode, step pulse as high as 20 and dir pulse up 5 with no improvement. My wires are not shielded.  This is my first post here. Sorry if i should have posted this elsewhere. PLEASE HELP ME!

Offline RICH

*
  • *
  •  7,331 7,331
    • View Profile
Re: stepper motor slow but still stalls
« Reply #1 on: May 21, 2016, 08:39:51 PM »
You need to tune the motors.
Steps  / Unit are calculated. What values do you have in Motor Tuning for the X & Y?

Post the mill x & y screw info. ie; screw pitch

You may want to increase the steps to 2000 on the drives. Stepper is 1.8 deg / 200 steps per rev so you micro step them at 2000.

Suggest  turn on switch 4 so there is no 1/2 current reduction when motor is at standstill. Shouldn't get hot.

Do you have info on the break out board?
Do have a manual for the drive?

BTW, post a link to stuff so one doesn't need to spend time searching for info.

---------------------------------
For now don't activate backlash.

You can use Mach3  to calibrate an axis.
Are you using MACH3?
Just follow the on screen directions. ( CTL J TAB lower left corner for calibration of axis).
Just move the axis some distance in the direction you will move before using the calibration feature to remove backlash.

Also make sure that the mill gibbs are adjusted and not too tight.

Lastly....READ the Mach Manual.

RICH
Re: stepper motor slow but still stalls
« Reply #2 on: May 22, 2016, 11:21:10 AM »
I have been reading the Mach3 manual and support a lot. I changed the X and Y motors to 2000 steps and my current x-axis settings are steps 80208.54 (after calibration), velocity 2.5 and acceleration 1 with step pulse 5 and direction pulse 5. On the y-axis steps are 74766.36 (after calibration) with velocity 1, acceleration 0.5, step pulse 5 and direction pulse 5. I still have brief stalls so my distances are inconsistent making calibration very difficult unless I do it by math and I figure steps should be 80,000/inch with my gear reduction and my screws turning 10 revolutions per inch for X and Y. My breakout board is labeled db25–1205 and a full description can be found at:www.nbglin.com/download/cnc25.pdf. My motor and driver are described at :www.wantmotor.com/product/Drivers/. I turned on switch 4 and zeroed out backlash. I am still dealing with low velocity and stalling. THANKS IN ADVANCE FOR ANY FURTHER HELP.

Offline RICH

*
  • *
  •  7,331 7,331
    • View Profile
Re: stepper motor slow but still stalls
« Reply #3 on: May 22, 2016, 12:57:45 PM »
Run the Driver Test? You will find the file in the MACH3 directory where you installed Mach.


Have you contacted Wantai?
What did they say?

RICH
Re: stepper motor slow but still stalls
« Reply #4 on: May 22, 2016, 06:33:38 PM »
I don't have the driver test file. How can I get it? I will contact Wantai.

Offline RICH

*
  • *
  •  7,331 7,331
    • View Profile
Re: stepper motor slow but still stalls
« Reply #5 on: May 22, 2016, 07:15:04 PM »
It is located in the directory where Mach 3 is installed and is part of  Mach3 installation.


RICH
Re: stepper motor slow but still stalls
« Reply #6 on: May 23, 2016, 10:06:25 PM »
My Mach3 directory has only two files: Mach3 loader and Uninstall Mach3. How can I get the driver check program?

Offline RICH

*
  • *
  •  7,331 7,331
    • View Profile
Re: stepper motor slow but still stalls
« Reply #7 on: May 23, 2016, 10:19:37 PM »
What version of windows are you using?

Do search for a file called   DriverTest    on your computer

RICH
« Last Edit: May 23, 2016, 10:22:17 PM by RICH »
Re: stepper motor slow but still stalls
« Reply #8 on: May 24, 2016, 11:31:04 PM »
Windows XP home edition on a Dell Dimension 4700 desktop. I downloaded Mach3 twice but do not see the program. Is there another way to get the program., Thanks again.

Offline RICH

*
  • *
  •  7,331 7,331
    • View Profile
Re: stepper motor slow but still stalls
« Reply #9 on: May 25, 2016, 07:51:46 AM »
Mach3 default installation is C:\Mach3. You should find the driver test  along with a lot of other files as shown in the attached.

RICH