Stepper motor vibrating but not turning

Hi everybody

I’m using 12v 6A power supply, I set the Drv8825 driver current to 0.7 and I put the the three jumpers under the deriver

The motor I’m using is
Model: 17HS8401
With step angel 1.8
size 48
Rated current (A)1.7
OHM 1.8
MH 3.2
Holding torque 52
Detent torque 2.6

I edited two lines in the code:
#define DEFAULT_AXIS_STEPS_PER_UNIT { 200, 200, 800, 200 }
To :
#define DEFAULT_AXIS_STEPS_PER_UNIT { 100, 100, 800, 100 }
And the bed size :
#define X_BED_SIZE 200
#define Y_BED_SIZE 200
#define X_BED_SIZE 1220
#define Y_BED_SIZE 2440

When I choose motion from the lcd screen options and try to move any axe the stepper motor viberate but doesn’t rotate :frowning:
What should I do to fix this problem?

First thing to check is your wiring make sure your wires are in the right order and all are connected. The vibrating motor is normally the magnets in the stepper firing in the wrong order.

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Have you set the vref on the drivers? Have you checked the voltage from the power supply? Incorrect vref was the issue the last time I saw a similar problem on the forum.

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I checked voltage from the power supply it’s 12 V
and I tuned the pin of the motor driver till the read on the voltmeter is 0.7

I didn’t ready your original post close enough since you already indicated you set the vref. One thing I notice in your picture is that you only have power to one of the two pairs of power-in connections. On a lot of boards, the motors are powered separately from the electronics, and many of the Ramps 1.4V wiring diagrams has power wired to both connections. You might try applying power to both pairs of 12V in connections.

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I connected power to all the four power-in connectors. Still the same problem

No firm ideas. The list of things from other forum posts:

  • Bad power supply (just because it reads 12V when not in use doesn’t make it good).
  • Blown stepper drivers. I’ve read that trying to move the motors without them connected can damage the stepper drivers. Disconnecting them while they are moving will certainly blow a driver.
  • VRef (though you’ve already checked this).
  • Wrong version of the firmware. (Unlikely, but if you were using CoreXY on a rectangular setup the steppers might fight each other).
  • Problem with the serial wring cable. Since there are only three drivers in the picture, I assume you are wiring your steppers in series. It is possible that you have the directions of the steppers reversed so they fight each other, but I would expect at least some movement if this is the issue.
  • Problem sending the g-code commands for movement. (not likely, but I include it anyway).
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Stepper motors have two coils internally. There are 4 pins on the motor connectors. Not all motors have the same pinouts in those connectors. With a multimter check you have a low ohm reading, about 3ohms, between adjacent pins in the plug that goes onto your RAMPS board, if the 3 ohm coils are between pins 1-3 and 2-4 then that is your problem. Remove the wires from 2 and 3 in that connector and swap them over.

Sorry if this is too simplistic but it is better to start at the beginning.

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Thanx alot for your effort but it was awire order

Thank you very much That was the solution :slight_smile:
But I still hear a tune in the motor after it rotates
How to make sure I’m connecting A to A and B to B

But I still hear a tune in the motor after it rotates

Thats normal, that’s the holding current that “makes” the holding torque. (don’t know how to say this in proper English)

How to make sure I’m connecting A to A and B to B

When the motor turns A is connected to A and B to B. If it turns the wrong way, just rotate the whole connection by 180 degrees

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Thanx for clearing :heart_eyes:

I have a stepper motor, but when I turn it on, the movement stutters and it does not work regularly (irregular steps).
What is the solution please?:pensive::pensive::pensive: