Stepper Motor Codes

I found a potential deal on stepper motors at my local hobby shop. They've got these Nema 17s (product code 17pm-k442-g4vs) listed as unipolar, but they only have 4 wires.

Am I correct in my assumption that 4 wires equals bipolar?

I'm trying to dig up a datasheet, but slow goings. Anyone know how to decipher the product code?

The code can be decoded at the manufacture's website or by using their datasheets. Ime, they're most often mfg specific, although once you read how they use them, it all makes sense.

They ARE listed as 1.8 degree, unipolar by Minebea (the mfg) I'll leave the rest to you. (see below)

Funny thing is, if you'd just googled the part number, you'd have seen they're Minebea motors, and had you then clicked the link, you'd have directly accessed the spec sheet that lists them.

Again, in the future try to google the part number (all by itself). Nine times out of ten, you'll find what you're looking for. I put the number in and it was the 2nd entry 1st returned page.

I don't have any experience using Minebea products, so please don't take my reply as a defacto recommendation.

Edited 1 time(s). Last edit at 02/26/2013 01:00AM by xiando.

Hmm... I did Google it, just as you did... the part number is 17pm-k442-g4vs.

On the link you found, there is data for 17pm-k442u and 17pm-k442b. So, please enlighten me: how do you turn "g4vs" into "u"?

(And thanks for the lecture!)

Also, what about the 4 wires? Ever seen a 4 wire unipolar stepper? I thought all unipolar steppers were 5, 6, or 8 wires? (Why don't you Google that and get back to me... I think this caper is a bit more complicated than your post implies).

Meh. it's close enough in my book. If you need specific details on a part number not shown in that document, contact Minebea directly. That was the point to my "lecture". This is what engineers, designers and end-users have to do, or they get screwed by all the "good deals" being offered by unscrupulous import export houses selling devices without clear accompanying documentation.

It was just advise, son. You can call it what you will, but I've been engineering for a living for 30 years, for NASA, for Boeing, for KLM, and for a variety of industrial concerns and and academic institutions. Take it or leave it. Not my concern in the long run.

good luck.

I contacted the manufacturer before posting -- they're slow. My question pertained the the code used for the serial.

And how is "g4vs" closer to "u" than "b"?

And how is a four wire stepper more likely unipolar?

30 years and no reading skills or deductive logic. Forum troll go away.

If you had said you "already contacted Minebea" and if you had even posted the name of the mfg in the initial post, I wouldn't have bothered to respond in the first place. I think you're full of it and didn't, at least not until I provided that info to you. As for your insult, well, son, I think you're a classic example of a leach. (since you decided to get ugly about it that is)

Edited 1 time(s). Last edit at 02/26/2013 10:54AM by xiando.

Believe what you want. I prefer "agile" to "waterfall" project planning, so I query multiple sources for the information I need simultaneously. They do love waterfall dev in aerospace, don't they?...

You haven't addressed any of the real questions I've posted (deciphering the code on these specific motors -- which is admittedly nontrivial -- and the fact that the motor has four wires; have you ever seen a 4-wire unipolar stepper? Is that possible? Please, dig into your 30 year archive and tell me.)

You have, however, been patronizing from the start.

So, wrapping up: I think I've got a bin full of 40N-cm bipolar steppers for $3 a piece. And I'm not giving you any. Na na, na na na.

Reply with whatever vitriol you like; this isn't productive. I'm done here.

Honestly, beyond this post, I don't intend to address any further questions from you, wherever they're posted. your attitude is typically adolescent and unworthy of my assistance.

As it's your hobby shop, can you measure these four wires? Unipolar motors have all four wires connected, on bipolar motors one wire has a connection to only one other wire, the other two wires are isolated.

@xiando: it's just a forum here. No need to get red in the face. You're not obliged to answer a question and if the questioner isn't satisfied with the answer you give anyways, it's his problem, not yours.

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Generation 7 Electronics	Teacup Firmware	RepRap DIY

The ending g4vs is a customer kode. I.e for special axel, gear and so on. I know this because i work with copy machines and they use alot off the same motors but with different gears on. :-)
So don't think about the g4vs.

If you look here u see that your motor is a 400nNm in unipolar setup and 500nNm in bipolar. (they should be hybrid motors as all others) :-)

[www.eminebea.com]

Some fine motors

Jesper

You can see it here in this Minebea Stepper Motor Part Number Decoding Table

[www.theprojectasylum.com]

@Kenzu: Thanks! Excellent info and exactly what I was looking for. I heard back from the manufacturer yesterday and they refused to give me the specs because it was a custom order.