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Adafruit Motor Shield V2 Stepper Integration
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Adafruit Motor Shield V2 Stepper Integration

by samirkazi on Mon Nov 25, 2019 10:47 pm

Hello,

I am currently working on a project that is using the Adafruit Motorshield V2 to control 2 stepper motors. The stepper motors are as follows:

Overview
https://en.nanotec.com/products/597-stf ... per-motor/
Datasheet
https://en.nanotec.com/fileadmin/files/ ... 0504-A.pdf

They say that they are rated to 0.5A at 12V, however even when just a single motor is plugged into the motorshield it causes the shield to fluctuate on and off and moves for very short durations of when the shield is on. I was under the impression that the shield is able to provide 1.2A to each stepper motor at 12V and so it should not be a problem. I am currently powering the motorshield externally with a 12V 3A power supply.

Would I need to change the motorshield or would adding capacitors help in this situation. I am not very good with electronics so any assistance on resolving this issue would be greatly appreciated!

Thank you in advance

samirkazi
 
Posts: 4
Joined: Mon Nov 25, 2019 10:33 pm

Re: Adafruit Motor Shield V2 Stepper Integration

by adafruit_support_bill on Tue Nov 26, 2019 6:51 am

They say that they are rated to 0.5A at 12V

That is not correct. The phase resistance is listed as 3.7 ohms, so the current draw per phase at 12v will be 3.24A. These motors are not compatible with the shield.
https://learn.adafruit.com/all-about-st ... he-stepper

adafruit_support_bill
 
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Re: Adafruit Motor Shield V2 Stepper Integration

by samirkazi on Tue Nov 26, 2019 9:24 am

Thank you for your quick reply Bill!

Is there anyway to hook up capacitors to make up for the lack of current supply from the motorshield? And if so would you need to add capacitors to each of the terminal outputs?

Thank you again in advance.

samirkazi
 
Posts: 4
Joined: Mon Nov 25, 2019 10:33 pm

Re: Adafruit Motor Shield V2 Stepper Integration

by adafruit_support_bill on Tue Nov 26, 2019 9:40 am

Based on the specifications, the motor appears to have been designed for use with a current-limiting "chopper" type driver. By using a high supply voltage and low-inductance windings, the motor will have better low-speed torque and can achieve higher step-rates. But it requires more sophisticated drive circuitry to control the current flow and prevent damage to the motor and/or driver. Common H-Bridge chips such as the L293D or the TB6612B as used on the shield are not suited for driving these high-performance motors.

The DRV8833 is a better match for that motor: https://www.adafruit.com/product/3297

adafruit_support_bill
 
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Re: Adafruit Motor Shield V2 Stepper Integration

by samirkazi on Tue Nov 26, 2019 7:44 pm

Thank you for the explanation Bill. I think the motors I selected will likely need to be changed. If you dont mind me asking a few more questions:

1) Does the board regulate voltages output to the stepper motor? or does that depend completely on the external power being provided to it? (For example if I use a 12V power supply but plug in 5V motors, will the board step that down)

2) To avoid purchasing incorrectly specced motors again, would you be able to advise if these would work with the board?

https://www.ebay.com/itm/DC-5V-Micro-10 ... 7aspn5kK-g

According to your previous calculations, at 5V and a resistance of 39 Ohms, they should only take 0.128A each much lower than the max of 1.2A per motor and so should have no issues running witht the board this time.

3) Finally for low current motors like the ones above, would it be possible to run a motor pair (2 motors) from the same terminals on the board (For example both motors split from the M1 and M2 ports on the board) so that they both rotate the exact same amount at the exact same time?

Thank you again in advance. You have been an amazing help so far!

samirkazi
 
Posts: 4
Joined: Mon Nov 25, 2019 10:33 pm

Re: Adafruit Motor Shield V2 Stepper Integration

by adafruit_support_bill on Tue Nov 26, 2019 9:39 pm

The drivers on the shield pass the supply voltage to the motor.

Those small motors would work with the shield. And their current draw is low enough that you could run 2 of them in parallel.

We also have these motors which are a good match for the shield: https://www.adafruit.com/product/324
They are rated for 12v, but will run as low as 5v with proportionally reduced torque.

adafruit_support_bill
 
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Re: Adafruit Motor Shield V2 Stepper Integration

by samirkazi on Thu Nov 28, 2019 12:50 pm

Thank you for all your help Bill!

I will look into the motors you linked as well. Thank you again. If I have more questions, I will post them here at a later date.

samirkazi
 
Posts: 4
Joined: Mon Nov 25, 2019 10:33 pm

Please be positive and constructive with your questions and comments.