[AndersG]

One of those "nice to know" bits. How do I find the inductance of these:
http://www.dalton.ax/stepper/P2260051.JPG

We have them up and running, just fine, but my inductance meter gives very weird readings. Not that it matters, it would just be nice to know.

[nthrower]

You will probably find that the inductance per winding changes dependent on where the rotor is. Inductance bridges normally us an AC signal, therefore the rotor position will alter the perceived inductance. I have some of these 5v motors from the 80's, and will dig one out of my spares box to check.

[AndersG]

OK. If I have the time, then I might hook up a tone-generator and do some measurements.

[dirtmover]

nthrower is correct. Think of a variable inductor, you change the inductance by varying the position of an iron dust slug. Your motor is behaving in exactly the same way as you move the rotor.

[MicroMill]

Mmmm. How about using something like a Fluke meter that measures inductance? I don't believe that the "inductance" will vary that much. "Inductive Reactance (XL)" however, will vary proportionately to the speed of the motor. (XL = 2*TT*F*L ). Where TT is my crude symbol for pi, and F = frequency. You can calculate F by using F=1/T(ime). If you have a calibrated oscilloscope, this should be fairly straightforward.

Jim

[AndersG]

I have a LC meter, similar to this:
http://py2wm.qsl.br/LC_meter/LC_meter-e.html

I think that the easiest is to hook up a signal generator and a scope and measure reactance at a given frequency. Not that it is very important. I was just curious.

[der_fisherman]

Have you looked here:-

http://www.mcsupplyco.com/uploads/Ma...s/Superior.asp
or
http://www.electrosales.com/warner/slosyn/index.htm
or
http://www.wimb.net/index.php?s=slosyn&page=4
or
http://www.artisan-scientific.com/in..._Datasheet.pdf
or
http://www.plctalk.net/qanda/showthread.php?t=893

I just Googled "Slo Syn Stepper motor" and got dozens of hits.

I cannot clearly read the type number on your motor, but I am sure that you can read it easier......

Why do you need the inductance? I usually get away with the max voltage and max current ........

I hope this helps you further.

Best wishes.

[AndersG]

From my webpage http://www.dalton.ax/stepper/
"The motors are Slo-Syn with 200 steps per revolution , 1100 oz.in. , 1.3v. 20A , type M113-FJ40"

Yes, I have Googled, but found nothing. And, no. I do not need the inductance for anything, except simulations i LTSpice.

I will check out the links you posted

PS. I now realise that I only posted the link to the actual pic, but the page itself. Sorry about that.

[KIMFAB]

Sorry, I see another error. Get rid of the smiley face to go the site.
All you might care about is the the resistance of the windings which is easily calculated.
The inductance is immaterial for the operation of the unit and will change as stated above.

[AndersG]

Done. Yes, I know. I was just being curious.

[KIMFAB]

Just looked at your site. Boy, I've seen and also made good stuff from junk but you take it to a new level by finding junk covered by mouse goodness. Congrats.

[AndersG]

True.. Why waste perfectly good equipment? There is one similar mill here, but without mouse poo, where the owner plans to interface Mach3 to the existing drivers. They are somewhat more recent. 2kHz choppers and 2n3055's.

Anyway. I found very few unipolar designs capable of high currents on the web, so I thought that someone else might find this useful.

[KIMFAB]

Here is my latest project. http://www.kimfab.com/images/vicon.jpg
May have to start a thread. Plasma table from the '80s got it moving on Mach 2 on an old computer. Going to try to make it work with Mach 3
Is that your home place in the pic at http://www.dalton.ax/?

[AndersG]

Wow! You must have a lot of extra space and an understanding spouse

Edit:
"Is that your home place in the pic at http://www.dalton.ax/?"

Yes, about 9M south of where we live. It is the Yacht club's place. A bit wetter than Nevada I guess

[KIMFAB]

Yea we haven't had reasonable rain for about 2 years. Sitting on 5 acres of choice desert.
My Finnish/Swedish wife was out here for the last bit and I showed her the picture. She said wow we gotta go there.
As for the understanding wife: I have lots of bushes and buildings around the house. Her attitude is: if I can't see it from the house it doesn't exist.

[AndersG]

From whereabout in Finland?

[KIMFAB]

Her grandfolks are from a small town at the northern end of the Finnish/Swedish border.
Came to USA in early 1900's

[AndersG]

OK. My great grand-father's brother jumped ship in New Orleans in 1911. Small world I guess. Never been to Nevada, but fairly close, California, Utah, Arizona and Oregon, plus sundry places like Florida, Minnesota, NY, Alaska, Hawaii, WA, LA..

Thread drift.. Sorry. I will stop here.

[KIMFAB]

You need to get on Skype. The folks at the top of the heap here at cnczone will probably shut this thread down since it no longer serves a useful purpose to the members.
Or send a PM. Good talking to you.

[rgammage]

Hello Anders

I am working on a design for a Unipolar driver with up to 7.5A drive which should work to 50v. I blew up the prototype, my fault, the design was OK and the second version was not so good. Now for V3! Will publish when finished.

Also know people who have found EMC2 to be more reliable than Mach3

Regards

Richard