I wish you a happy new year.
I am trying to control a stepper motor accoriding to this tutorial. http://electronics-diy.com/electronics/stepper_motors.php
Few days ago, I used a motor which draws 2A current and I failed to control the motor using darlington ULN2003 chips.
And, this time, I changed a motor which has a speficiation as below.
*Motor Specification
Voltage : 8.6V
Current : 1.0A/Phase
Resistance : 8.6ohm/Phase
Inductance : 18mH/Phase
Holding torque : 13.5kgf
It draws 1A at 8.6V but I failed again.
The motor only buzzes just like the situation with 2amp stepper.
Could please someone advise me what seems to be wrong?
If the motor buzzes, you might be trying to send steps too quickly for it. Try slowing down the rate of stepping to maybe two steps per second, to be sure.
thank you for posting your idea and I wish you a happy new year.
i am not sure where each pins should be fixed to ULN2003 pins because, the color of the wires are different from the drawing.
Please check this drawing. http://www.flickr.com/photos/23525729@N06/3153889026/
It specifies the color of each wires, but the new motor I have has different wire colors.
There is black and blue but the rest of the 4 wires are totally different compare to the previous stepper motor I controlled successfully.
Please see below links.
This is a picture of previous stepper motor i controlled successfully. http://www.flickr.com/photos/23525729@N06/3155532330/
And, this is the new one which I have a problem with. http://www.flickr.com/photos/23525729@N06/3154695313/
So, as a matter of fact, i don't know how i should put those wires on ULN2003.
I tried to put all kinds of way by exchanging each wires but there are so many configuration possibilities... ;D
The seller of stepper motor is on a holiday throughout this week, so I can't call him for an answer either.
Yes, I tried to slow down the number of stepps per second by reducing the number of steps in the software and I successfully controlled it with my previous motor.
but, I feel nothing from the new one when i connect it to ULN2003.
P.S.
The drawing is as same as the previous motor.
yeah here's what i do find the 2 "common wires" some unipolar stepper motors have 1.
connect ohm meter wire to common wire, and then u can find out which wires are on the exit side of the common wire
let's say that on the picture above, left side: connect ohm meter to common wire and one of "coil ends". You may get 50ohms, and connecting ohm meter to both "coil ends" you'd get 100 ohms
Yes!!! Now, the motor shaft is spinning.
Thank you very much for advising me.
Currently, although the motor is spinning, it buzzes in the middle of stepping.
My motor's stepping degree is 1.8 so one full revolution is 200 steps.
I tested with full 200 steps.
When I do this, the motor buzzes for a second and this kind of buzzing action happends whenever the motor tries to start and in the middle of its spinning.
It looks like something is grabbing the shaft to prevent it from being rotated.
I supply 8~9VDC power(using adapter) to ULN2003 at the moment.
Does it something to do with supplying voltage?
I mean, is my motor vibrating because ULN2003 needs more power?
According to this tutorial http://electronics-diy.com/electronics/stepper_motors.php
the supply voltage is 12~24V.
Then, should I supply such high voltage regardless of my motor's operating voltage(8.6V for new motor)?
My first stepper motor which has a specification as below was controlled easily whether I use 1.5V batteries or adapter.
*voltage : 4V
*current : 0.95A
*resistance : 4.2ohm
*inductance : 3.3mh
*holding torque : 1.6kgf
Hi, I have been keep testing the motors.
In case I reduce the speed of the motor, the motor spins fine. No buzzing at all.
But, that is the case when I set the speed at 30rpm and 100steps(which is the half of full revolution of my motors).
So, this is too slow and short stepping for my application.
I need to increase the speed as well as the number of stepping.
Could you advise me how much voltage and current should I supply to ULN2003 chips in order use the motors with increased speed and steps?
Stepper motors are really not meant to run very fast. Most stepper motors will starrt to vibrate and make a lot of noise if they runn too fast. Or they will not run at all.
