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[on:]

Hello all,

I'm new here, and new to Arduino (Coming from Basic Stamp).  Anyways, I am making an attempt to control a high voltage (~48V), high current (~6A), bipolar (4 Wires) stepper motor.  The motor can be seen here, which has data sheets and what not:  http://www.automationdirect.com/adc/Shopping/Catalog/Motion_Control/Stepper_Systems/Motors_-z-_Cables/STP-MTRH-23079

I understand how to drive a stepper motor, and I have found the bipolar schematics on the Arduino library, but none of the solutions handle a motor this big.  Most drivers use the SN754410 or L293 from what I've seen.  I have also noticed stacking of the SN754410 chips for higher current ratings, but I suppose I would need 6 of them, and they still will not handle 48V.

Would I have to build my own dual h-bridge from NPN Transistors or MOSFETS?  Does anyone have an example circuit that has some protective features, such as the back current diodes.  Would this be enough protection to avoid damage to the Arduino?  I would also like to keep this relatively cost efficient.

Thanks in advance!  I hope I made everything clear.

[Reply #1 on:]

These people sell kits and ready built up drives for that sort of thing if you don't want to build your own:-
http://www.diycnc.co.uk/

[Reply #2 on:]

Thank you, I'll definitely take a look.

I'm more interested in building my own, both as a learning experience and to keep cost as low as possible.

Tony

[Reply #3 on:]

You have a $45 motor that needs a $200 driver. It's a 4 wire unit so you can't drive it any way /other/ than bipolar. If it were a 5 6 or 8 wire motor, you could build a simple unipolar driver with discreet components which would work... and open source designs for those are available. e.g. pminmo.com has the Mardus-Kreutz which (I think) manages up to 8 amps. Anyway, won't work on a 4 wire motor.

The part that amazes me is how little torque that motor is rated for given the amperage it needs. 286 oz-in is really not that much... You can get that from a KL23H286-20-8B at 2.8 amps per phase in unipolar mode with any number of open source drivers.
http://www.google.com/search?q=Keling%20Technology%20Inc%20%22KL23H286-20-8B%22

I keep a list of known good motors at:
http://techref.massmind.org/techref/io/stepper/linistep/motors.htm just in case that helps.

Building a high amperage bipolar driver yourself is going to be a "fun" experience. There are a few designs around, but I'm not sure how proven they are. For example:
http://www.piclist.com/techref/io/stepper/hipwrbp-gm.htm (looks ok, not sure if it was ever actually built)

http://www.cnczone.com/forums/open_source_controller_boards/13451-high_current_bipolar_stepper_drive.html (the authors sudden silence is not encouraging)

It it were me, I'd buy a different motor... or buy a geckodrive. Good luck and best wishes and please let us know how it works out?

[Reply #4 on:]

Thank you for the detailed response.

I actually don't really care if it is a stepper motor or not.  I've just been having trouble finding a motor around that torque range and around 300 rpm.  I've searched for gear motors, but all the ones that meet the requirements are around $350 and up.  That particular stepper motor is only $40.  Actually, I would REALLY prefer a dual output motor that meets the above torque and rpm range.

I'll browse around the list of motors you provided to see if there are any better alternatives.

I keep reading about H-bridges and how a simple dual h-bridge setup will drive a bipolar stepper motor pretty easily.  I have found plenty of tutorials, but I'm just lacking the knowledge to adapt it to the higher power requirements.  Most tutorials build the controller for around $20 or so.

Thanks again.  Anymore advice will be greatly appreciated.