Stepper motor question

[Tricka90]

Good morning everyone,

I've been studying stepper motor functioning in order to choose the right one for my application with proper control board.
Before buying I wanted to ask your opinion just to make sure I'm buying the right things.
I need a motor capable of exerting a 20 Nm torque when spinning at 10 RPM or lower.
I've choosen the following motor which has an Holding Torque of 23 Nm.
**broken link removed**
If I got it right, the Holding Torque should be the torque that the motor is able to apply when it is not rotating, and it is the maximum torque it tends to as RPM decreases. So this motor should be ok, isn't it?
Furthermore, the motor needs a Rate Current of 6A, so I'm considering to buy the following control board:
**broken link removed**
which can supply a Peak Current of 7.8A, so it should be sufficient to properly power the motor.
Do you think all my reasoning is correct and I can buy the two items I've linked?

Thanks so much to anyone will give me some advices.

 

[KlausST]

Hi,

I´d say you are close to the limit. For my taste too close.

20Nm expected rotating current of a 23Nm rated holding current motor is not much headroom. And the motor will allways run at it´s upper current limit and thus on its upper temperature limit.
Half the current will result in a quarter of temperature rise. (A not moving motor with 6A current will generate the same heat in it´s windings as a full speed moving motor with 6A current)

Check if the control board can operate at 6A continous current ... and take ambient temperature, and reduced heatsink efficiency into account. (dirt, reduced air flow...)

Klaus

 

[FredCailloux]

My answer is not one based on electronic specifications and engineering point of view but rather simple common sense, and it goes like this. I would never buy Any product from a company for which I cannot reach and have the address in case I need support from their customer service, at any cost. Your motor is from JiangSu WanTai Motor Co.,Ltd. I don't know them other then their web site will not be able to give Any information about address or company profile and the like.

If you cannot reach them how do you figure you will be able to get help from these people? I say, pay more but get support with it.

Same goes for the driver, but here at least Deitech will display their company information including a phone number. Give them a call and ask a clever technical question and see how they answer. You may be surprised how sometime you can judge the quality of a supplier from how intelligent their answer are. If they cannot answer properly they will not be able to help you in case of problems.

 

[DNA Robotics]

Actual turning torque is a LOT less than holding torque.