DRV8825 and 5.5Ohm stepper motor

Hello
I have a stepper motor that does nothing when connected to my DRV8825, no matter the current
The setup works OK with another motor and the motor works when connected to a L298 bridge
Only this particular motor with the DRV8825 does not work…
The only difference that I have noticed is that the motor that does not work with it is 5.5Ohm, and the motor that works with it is 3.7Ohm
Any clue? There’s no spec on the motors themselves
Thanks

Hello.

Can you post more information about your system? How are you controlling the DRV8825 carrier? What are you using as a power supply?

Are there any identifying marks on the motor that you might be able use to search for some kind of datasheet? Do you have a link to where you got it?

Also, can you post pictures of your setup that show all of your connections?

Brandon

Hello and thanks for the reply
I’m sending pulses to the STP pin with an Arduino, and my supply is 9V 5A
As I said, the motor works fine with a L298 but not with the DRV8825 and the DRV8825 works fine with another motor
Yes there is marking on the motor that does not work, but I couldn’t find anything on it (it comes from an old scanner and I can’t user another one)


Concerning the connections, there’s SLP and RST pulled high, UMOT and GND to my supply with a capacitor, the other ground to my Arduino’s ground, the STP to my Arduino digital pin, and the coils of the motor at their designated spot. This setup is working fine with another mother, but not with this particular one.

Thanks for the additional information. Without any motor specifications to work from, it is difficult to do any meaningful troubleshooting or say whether the DRV8825 carrier is appropriate for use with that motor. The connections you mentioned sound fine, and if the driver is working with your other motor, I suspect your Arduino program is working as expected. How many leads does your stepper motor have? You might double check that you have the correct pairs of wires for each coil. What happens when you send step signals to the driver (e.g. are there any signs of life from the motor, is it even holding its position)?

Brandon

Hello and sorry for the late reply
There’s 4 wires coming out of the motor and I checked again and the coils are in the order A-B-A-B
There’'s no sign of life from the motor whatever I do with a 1.8A current and sufficient cooling, the DRV8825 just gets warm and the moitor does not hold its position

Thanks for posting that additional information. It might be possible that the voltage and current limit combination you are using is not appropriate for that stepper motor; however, as I mentioned before, it is difficult to do any meaningful troubleshooting without knowing the specifications of the motor.

Brandon