Stepper motor problem

Other Hardware Motors, Mechanics, Power and CNC
1

Hello, a few days ago I bought a stepper motor, since it's used the serial number is ruined and i can't find any information about it.

To control the motor I'm using an Arduino uno board and a l298n driver board, I'm using a 12V 3A power supply to power everything.

I used mainly the "stepper_oneRevolution" and "stepper_oneStepAtATime" standard sketch but the motor work (inconsistently) for like 2-3 revolution and then it stops and starts to shake.

I used this to connect the motor to the driver board and the rest of the wires are connected as in this image

Thanks in advance for the help, sorry if I make silly mistakes but it's the first time I use stepper motors.

2

Assume nothing, measure the windings with the resistance range of a multimeter. The resistance of the
windings will determine how it can be driven. If its 10 ohms or less you are probably limited to constant
current drivers like the DRV8825. If 30 or 40 ohms range it can be voltage driven from an L298N at 12V,
but it will be slow. Trying to voltage drive a current-controlled motor(*) severely limits the achievable speed.

But you also need to know how much current the motor needs - what size is it? The max current is usually
determined by thermal considerations, although some older steppers are destroyed by overcurrent (the
permanent magnets are weak and can be de/remagnetized by over current.)

(*) steppers are designed to be current driven.

3

The resistance of the windings is 10 ohms but I don't think I have the tools to measure how much current the motor need.

Here is an image of what I'm working on

4

Then as Mark said:-

f its 10 ohms or less you are probably limited to constant current drivers like the DRV8825.

You post images like this image guide not on some off site thing that needs an account.

Is the motor getting hot?

5

Grumpy_Mike:
Then as Mark said:-
You post images like this image guide not on some off site thing that needs an account.

I tried to upload a picture that way but I get an error message even if I did everything correctly

Grumpy_Mike:
Then as Mark said:-
Is the motor getting hot?

No, only the driver gets really hot in a few seconds

6

I tried to upload a picture that way but I get an error message even if I did everything correctly

No you did not do everything correctly, that is why it didn't work.

only the driver gets really hot in a few seconds

That means it is trying to pass too much current. That driver is not good enough to drive your motor you need a current limiting driver.

7

DRV8825 probably what you need. If you can't managed uploading a photo, at least describe the motor
diameter, length and weight, that is very useful information.

8

The motor is 5cm long ant it has a diameter of 5.5 cm. I bought these parts to learn the functioning of stepper motors without damaging the components that will go into my project but apparently I bought the wrong components. I'll write another post to ask for advice on the components that fit my final project so there is no risk of buying the wrong components.

9

So roughly the size of short NEMA23 motor - perhaps try giving it 5W. power = I-squared-R

10

Hi,
If you couldn'd upload your picture.
How big is it?
What format?
Keep its size to under 1M, use PAINT to resize if necessary, about 1000 pixels wide is good.

Tom... :slight_smile: