Stepper Motor Question

• posted

Hi all, Say I have a stepper motor whose ratings say that it rotates

1.8deg/step. Does that mean 1.8 degs as in Full Step mode or as in Half Step Mode? I mean: Will it rotate at 3.6 deg/step in Full-step mode or will it rotate at 0.9deg/step in Half-Step Mode?

Another question: I know that in order to get a stepper motor rotating u need to give it a sequence of pulses as input. Say I just connect one phase to a battery(that is, only one pulse). Will it just rotate by one step and stop?

Thanx,

Karthik Ravikanti

```--
Let there be Sound!```
• posted

Hi all, Say I have a stepper motor whose ratings say that it rotates

1.8deg/step. Does that mean 1.8 degs as in Full Step mode or as in Half Step Mode? I mean: Will it rotate at 3.6 deg/step in Full-step mode or will it rotate at 0.9deg/step in Half-Step Mode?

Another question: I know that in order to get a stepper motor rotating u need to give it a sequence of pulses as input. Say I just connect one phase to a battery(that is, only one pulse). Will it just rotate by one step and stop?

Thanx,

Karthik Ravikanti

```--
Let there be Sound!```
• posted

Hi.

It means 1.8 degrees per full step.

The latter.

It is more useful to think of the motor as responding to electrical phase changes. The motor will tend to follow those changes, which occur in steps, not pulses.

It might not rotate at all, or it could rotate most of two full steps. It would depend on what the rotor position was before you energized the single coil. That energization would define one of the electrical phase positions midway between some adjacent full step positions. The rotor will settle at that position. Whether it has to move to settle there would depend on the starting position.

Welcome.

```--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com```
• posted

It's the first hit here:

Good Luck! Rich

• posted

------------ Bill Sloman, Nijmegen

• posted

```--
Except for this part:  "The reactance (inductance and resistance) of
the motor windings limits the current flowing through them."```
• posted

So how would you express that particular truism?

----------- Bill Sloman, Nijmegen

• posted

```--
The impedance (inductive reactance and resistance) of
the motor windings limits the current flowing through them.```
• posted

And if the motor moves, the generated EMF also takes part in limiting the current

• posted

I like the way you said "if" :-)

```--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more```
• posted

As an editor, you seem to have mastered the nit-picking about the choice of words, but you don't seem to be able to produce an alternative sentence, which would seem to be the more important task in the business of providing constructive criticism.

---------- Bill Sloman, Nijmegen

• posted

As is mentioned on the Jones' web-site.

------------ Bill Sloman, Nijmegen

• posted

```--
Thanks, Bill.  It seems that in your eyes and in one swell foop I've
been upgraded from a Texan ignoramus to a master editor, of sorts...```
• posted

If you were of the stuff which editors are made of, you'd have recognised that I wasn't too impressed with your editorial skills.

If you had, in fact, posted a complete sentence, I might have been able to work this out. All that was obvious from what you posted was that you preferred "impedance" to "reactance" which is fair enough as trivial nit-picking goes, but scarcely worth posting.

The "error" - such as it is - doesn't impair the usefulness of the web-page, and thus doesn't justify a public comment.

If you'd confined yourself to sending your criticism to Jones, you might just aspire to be in a position to lecture me about the meaning of the word "gracious".

------------- Bill Sloman, Nijmegen

• posted

```--
Be that as it may, Sams Technical Publications seems to to have a
different impression since I recently finished, and was paid for,```
• posted

"John Fields" schreef in bericht news: snipped-for-privacy@4ax.com...

On reading this I checked your posting via my providers news server and I found that you had indeed posted a complete sentence. I'd responded to what I'd seen on Google Groups, where the last half of the sentence wasn't displayed. I apologise for blaming you for a fault in Google Groups.

Sure there's a difference, but it isn't an error that misleads the reader.

I distinguish between errors that misdirect the reader, and those which only need to be corrected for reasons of technical pride. Misleading information has to be corrected - typos and similar errors can be left to the author to correct, if they can be bothered.

I must say that I regret being offensive to you when I should have been offensive about Google Groups - a clear case of misdirected efort.

---------- Bill Sloman, Nijmegen

• posted

My God, This thread was supposed be about my teeny-weeny question on stepper motors. But now when I return to it, the topic switches over to editing,Google Groups, and all. I am really new to newsgroups and forums, seriously I wonder how do you guys find the time to respond to complete strangers so *illustratively* on even apparently unrelated topics!

newways....;)

Karthik Ravikanti