help with my stepper motors

[mocnc]

Hi, I am needing some help with figuring out what my stepper motors are.....they were given to me so i am hoping this time a free item is just what I need. They are a Sanyo Denki "Step-Syn" type 103G770-1848, 3.5vdc, 1.5amps, with 1.8 deg/step. They are a 6 wire motor (brown,red,yellow,blue,orange,white). I am in the process in building jgro's cnc, with a work area of about 12" by 40" I am hoping to cut wood, plastic, and some thin soft metals. I have searched the internet and haven't found the info on these stepper motors. I was hoping someone here may know what the oz/inch is and how should I wire these. I know it may be a long shot, but I am out of resources.

[Torchhead]

Being 6 wire they will work with bipolar or unipolar drives. They will probably end up being in the 80 to 120 oz-in range. To find the windings take an ohmmeter and measure between one wire and all of the others. There will be two more that show resistance. Group those three together. Now turn your ohmmeter to the lowest scale. In each bundle of three wires find the wire that measures 1/2 the ohms from either of the other two in the group. That one is the center tap. Write down the color codes. Now find the center tap on the other group of three. Now you have all the info you need.

I would suggest looking at the the Xylotex 3 or 4 axis stepper cards. They are bipolar drives so you would not use the center tap on either winding. They are microstepping (smoothes out the steps) and a chopper type with adjustable current limiting

Stepper are current devices and you use higher voltage to make them spin faster using a chopper current limited drive. You need to keep the current down close to the 1.5 A rating but use 24VDC with the Xylotex to get better RPM.

The motors will help you refine your machine. If they are too wimpy to do the work you want at reasonable speeds you can upgrage the motors to some of the new hybrid steppers that will have about 3 to 4 times the torque in the same footprint (23 frame). Xylotex will still drive them.

We also sell an electronics package with all of the interface and motor driver (Xylotex). We are starting to sell motors too so an upgrade would be easy.

Tom Caudle
www.CANDCNC.com