Stepper motor voltage

[waldir]

Hi,
I just got my first stepper motor, a Sanyo Denki 103H5210-0440. According to the specifications notes ( http://www.active-robots.com/products/motorsandwheels/stepper-motors/datasheets/103h5210-0440.pdf ), it should receive 3.96V at 1.2A/phase.
However, one of the manufacturer's detailed description shows graph of the torque at 24V and 36V (page 71 of this 3MB document: http://www.motiononline.com/SDC_PDFs/2step_e1.pdf#search=%22103H5210-0440%22 ).

So... what should I connect this motor to? Is the voltage not important?

Thanks
waldir

[Admin]

The chart on the motiononline.com datasheet (page 6) says that you need DC24V to operate the 2-Phase driver. The high voltage is for the driver circuitry, not the 4V stepper.

Anyway, the 24V is applied to the driver, and it steps down the voltage to drive your stepper. Check the pintout schematic on the driver to make sure.

. . . but in my humble opinion its kind of lame to carry 24V batteries on a robot for a 4V stepper . . . I guess they designed the driver that way to handle many different types of stepper motors.

You should consider maybe using a stepper driver IC that operates around the 4-7V range.

[waldir]

Oh, thanks for the explanation!

I'm about to experiment with this stepper driver: http://www.active-robots.com/products/motorcon/active-stepper.shtml

Am I right in thinking that I should connect my 7.2V battery in series with a 2.7 ohm resistor (added to the 3.3 Ohm/phase of the motor, it gives the 1.2A consumed by the motor)?

Thanks,
waldir

[Admin]

No, you dont need to add any resistors. The extra voltage will just overdrive your steppers a bit.

About overdriving, you should read my DC motor tutorial:
http://www.societyofrobots.com/actuators_dcmotors.shtml

Steppers and DC motors are basically the same when it comes to voltage rating.

[waldir]

Thanks !

That's very nice of you to have helped me so quickly

waldir