What and how with these motors?

[Witsenburg]

Hi,

I just bought a cheap second hand motor with a damaged sticker on the side. It still says Japan se... so I guess it is a Japan Servo Co Ltd. motor. Looking at their site, the external dimensions and the coil resistance, I think I have a KH56JM2-913, with 6 wires. Here's the specsheet:
http://www.japanservo.com/digital/general/pdf/KH56J.pdf
Now for the questions:
How do I connect these to a bipolar driver? Just just the outer 2 terminals of each coil and leave the middle one untouched?
What amps and voltage can I run them on in bipolar mode?
Thanks,

Hugo

[rodneydeeeee]

Have you tried contacting them directly via email? They may not help though being its all about money anymore.

[Madclicker]

There are at least 2 ways to wire them to a bipolar drive. The way you described is called series connected. Another way is to use the center tap with an outer lead...called half winding connected. Series will give most low end torque and half winding has better high end response.

In my research to write a DIY guide I found a reference to another way to connect them. I won't repeat it until I confirm, but if it is valid it would allow 5 wire unipolar motors to be connected to a bipolar drive.

[Oldmanandhistoy]

In my research to write a DIY guide I found a reference to another way to connect them. I won't repeat it until I confirm, but if it is valid it would allow 5 wire unipolar motors to be connected to a bipolar drive.

Hi,

Would be interested to know how to wire a 5 lead motor; at this link it says it’s not possible. http://www.wimb.net/index.php?s=motion&page=52

Do you have a link?

John

[Witsenburg]

... The way you described is called series connected... Series will give most low end torque and half winding has better high end response.

OK, I prefer torque over speed in my application. Would this mean 9 ohm over the coils, 1 amp (that doesn't change when you put them in series, doesn't it?), so 9V to drive them?

Thanks,

Hugo

[CNCkitsandBITS]

Unipolar motor and you want to run it bipolar series then the current rating will be 0.707 of the name plate current rating. So for this motor if I have read the pdf correctly set current to 0.707 A/phase and voltage can be up to 98v (up to 20 times name plate rating).

Wiring, refer to the link in post #4

[Witsenburg]

Eh, that bit I don't understand. If a coil has a certain resistance and a maximum amount of amps going through it, doesn't that determine voltage? I learned V = I x R, a long time ago.

And reducing the amps to 0.707, would that give a reduction in torque? My whole reason to wire it bipolar is to increase torque!

Cheers,

Hugo

[mcpltd]

If the motor is 0.5Nm in unipolar at 1A the rated curretn in series is 0.7A, but you will get slightly more holding torque than the Unipolar rating.
But this motor is goingto have a lot of inductance and what ever driver you have will find it had getting the motor running to a good speed.
Also high inductance motors can damage some drivers.

Eh, that bit I don't understand. If a coil has a certain resistance and a maximum amount of amps going through it, doesn't that determine voltage? I learned V = I x R, a long time ago.

And reducing the amps to 0.707, would that give a reduction in torque? My whole reason to wire it bipolar is to increase torque!

Cheers,

Hugo

[mcpltd]

You could remove the back of the motor and cut the link between the centre taps.
This woud make the motor a 4 wire motor.

Hi,

Would be interested to know how to wire a 5 lead motor; at this link it says it’s not possible. http://www.wimb.net/index.php?s=motion&page=52

Do you have a link?

John

[Witsenburg]

This is all pretty weird to me, but anywho, I have this motor so I want to use it. I don't care much for speed, as this motor will drive the Z-axis of my 3d router and I only route contours. So, every once in a while I change cutting depth, but after doing that I continue cutting a contour 2d only. I even considered making the z-axis manual and putting stops in the g-code program, but that would be stupid. I use M16x1,5 threat on the z-axis and prefer direct drive. Routing in steps of max 9 mm, that would mean 6 revolutions, so 6 x 180 steps is 1080 steps. If it can do that acurately in say 3 or 4 second, I'm happy. That's only 270 - 360 full steps a second. Mr. Motion control products, since I'm mailing with you about this motor and you MSD524 driver; would your driver be up to that?

Cheers,

Hugo

[mcpltd]

Ok, so as you mentioned speed is not an issue.
Yes this motor should be fine with the MSD542.

This is all pretty weird to me, but anywho, I have this motor so I want to use it. I don't care much for speed, as this motor will drive the Z-axis of my 3d router and I only route contours. So, every once in a while I change cutting depth, but after doing that I continue cutting a contour 2d only. I even considered making the z-axis manual and putting stops in the g-code program, but that would be stupid. I use M16x1,5 threat on the z-axis and prefer direct drive. Routing in steps of max 9 mm, that would mean 6 revolutions, so 6 x 180 steps is 1080 steps. If it can do that acurately in say 3 or 4 second, I'm happy. That's only 270 - 360 full steps a second. Mr. Motion control products, since I'm mailing with you about this motor and you MSD524 driver; would your driver be up to that?

Cheers,

Hugo

[Madclicker]

Hi,

Would be interested to know how to wire a 5 lead motor; at this link it says it’s not possible. http://www.wimb.net/index.php?s=motion&page=52

Do you have a link?

John

That's the way I always thought it was. Like I said, I didn't want to repeat this until I checked it out, but the more I think about it the more I think it might work. Basically use just the low side of the bipolar drive transistors to sink the current.

http://www.motiongroup.com/steppermotors_basics.shtml