Hey,
This is my first post here. I'm a new machinist, been around a shop for about a year now. I'll post the rest of the story later, but for now... onto the problem.

I've got 3 stepper motors that I'm trying to find/build a controller for. The problem is that I have little experience in electrical/onics stuff. My motors are Cetronic model HY200 2226 0470 ACM8. A datasheet can be found HERE (http://www.cetronic.co.uk/pdf/stepper_motors/HY%20200%202226.pdf). Now, if I'm reading it right, my motor is rated at 4.7 Amps. It doesn't give a recommended voltage, just a max of 75V. Now googling for other steppers of related torgue and amperage I suppose that the voltage will be extremely low, like 2 or so volts... but I don't really know.

My biggest problem is that I can't seem to find any controllers that are rated that high of amperage. I even looked around for some darlington pair transistors and can't find any that I believe I could use.

Any help appreciated. Pointing me to some (preferably cheap) stepper controllers that would be suitable, or some transistors that could be used in conjunction with a low current logic circuit would be great.

Geckos will work. Not very cheap, but they work.

Rated voltage = current x resistance. 4.7*.33=1.55V

A member here is developing an inexpensive 5A drive that may be available in the next few months, if not sooner.
http://www.cnczone.com/forums/showthread.php?t=33756

Ya, saw Geckos from the abundance of adds from it on the site... expensive is putting them lightly.

Thanks Ger, I noticed that shortly after I posted this, looks interesting.

If you need the power, then Geckos or MCP are the only answers to do it right at this point.

However, if you are not requiring that (quite large) amount of power and speed, just don't use those particular steppers. I hate to say it, but quite honestly a reasonably sized controller AND three or four steppers matched to it is still only a fraction of the cost of getting just the drivers needed to drive the motors you have. Depending on the size of the application, you may want to think about going that route instead.

If you really do need that kind of fast response and power, just bite the bullet for the Geckos or Motion Control drivers and you won't be disappointed.