Unusual stepper motor

Hi.
I have a bipolar motor (PM20S-020). I found strange thing - it's spinning by 2 wires not 4. So if I connect first 2 it's spinning clockwise. If I connect another 2 it's spinning counterclockwise. There no matter pole of wires it's be spinning in one way. That's all. There no need 4 wires connect in one time. Especially it's no need because if I connect 4 wires in one time motor will not spinning: first wires spin it clockwise second wires counterclockwise. But for work I should (I do) use driver. I have L293DNE. Can you tell me more about this type of motor? It's still call "stepper"?

Hi,
Some info here: http://www.nmbtc.com/pdf/motors/PM20S020.pdf This shows 6 wires.

What software sketch are you using? Need more information.

I think it is a stepper motor.
You can check how to connect it on this page : http://www.ermicro.com/blog/?p=423 (search for "stepper").

terryking228:
Hi,
Some info here: http://www.nmbtc.com/pdf/motors/PM20S020.pdf This shows 6 wires.

What software sketch are you using? Need more information.

Hi.
This is incorrect datasheet for my motor. There info about unipolar motor but fifth wire is ground of CASE of motor. So fifth wire not interconnect to anything. And others wires connect to each other by pair (1 to 2 and 3 to 4). That's all. First time I'm too thought that it's unipolar motor and I had problem with that :slight_smile:

Peter_n:
I think it is a stepper motor.
You can check how to connect it on this page : http://www.ermicro.com/blog/?p=423 (search for "stepper").

There a lot of common info about steppers. And this info not correct fully for me because it's common info and I knew that. A little bit not coincide for me. What I should look for?

If it spins when you connect the two wires directly to a battery then it is not a stepper motor.

If it spins because some Arduino program is doing something then we can't very well help if you don't post the program code.

...R

Robin2:
If it spins when you connect the two wires directly to a battery then it is not a stepper motor.

If it spins because some Arduino program is doing something then we can’t very well help if you don’t post the program code.

…R

No. If it’s connect directly to a battery it will do only one step.

My code is simple:

#include <Stepper.h>
Stepper myStepper(20, 3,4,5,6);            

void setup() {
}

void loop() {
  myStepper.step(1);
  delay(30);
}

If it has 5 wires it may be a unipolar motor.
measure the resistance across the winding and from the 5th wire to each of the other 4 wires and post the results.

raschemmel:
If it has 5 wires it may be a unipolar motor.
measure the resistance across the winding and from the 5th wire to each of the other 4 wires and post the results.

I said before. Fifth wire not interconnect to other wires. It just connect to case of motor (like a ground). Between pairs (1 and 2, 3 and 4) about 8ohm.

Here info that it's bipolar chopper. What does mean: chopper?

And there says that I need a UDN2916B-V controller. I have L293 it can be enough?

This was your only original question:

Can you tell me more about this type of motor? It's still call "stepper"?

until you asked about the "chopper"

Bipolar chopper drive: drive that uses the switch mode method to control motor current and polarity.

Glossary - A through E - Empire Magnetics Inc. chopper drive

What exactly do you need. You already said you have the motor turning. Now you know what a chopper drive is. Why exactly are you posting ? Is this just an exercise in curiosity or do you need help ?

raschemmel:
or do you need help ?

I need help. I want to know how to control this motor correctly with L293 and arduino?

First of all I want to know how to de-energize the motor when it's not work with library Stepper.h? Because it so hot even it's stop.

EDIT: for "hot" problem I invented solution. I just added a resistor about 100 ohm to output of motor. Now it has less torque moment but its enough for me and not warming

The windings are 50 ohms so two of them running from a 12V supply is about 25 ohm load which is about 0.5 A.
The L293 enable pins need to be HIGH and then you need to energize the windings by using the correct stepper phase sequence.

If you think of the four Direction Input lines for the L293 as
A B C D
or
D C B A

then
D C B A

1 0 0 1 (9 DEC)
1 1 0 0 (10 DEC)
0 1 1 0 (6 DEC)
0 0 1 1 (3 DEC)

so the FULL STEP SEQUENCE is 9 ,10, 6, 3 (DEC)

and the HALF STEP SEQUENCE is:
8, 10, 4, 6, 2, 3, 1 ,9 (DEC)

If you google " arduino stepper motor code example"

you will find sketchs that consist of a series of

// 9 DEC
digitalWrite(DIR_D, HIGH);  
digitalWrite(DIR_C, LOW;
digitalWrite(DIR_B,  LOW);
digitalWrite(DIR_A, HIGH);
delayMicroseconds(100);
// 10 DEC
digitalWrite(DIR_D, HIGH);  
digitalWrite(DIR_C, HIGH;
digitalWrite(DIR_B,  LOW);
digitalWrite(DIR_A, LOW);
delayMicroseconds(100);

etc., etc. etc.

If you look at the Stepper.cpp file in the stepper Library what do you think you are going to find ?

MaximDroy:
Hi.
I have a bipolar motor (PM20S-020). I found strange thing - it's spinning by 2 wires not 4. So if I connect first 2 it's spinning clockwise. If I connect another 2 it's spinning counterclockwise. There no matter pole of wires it's be spinning in one way. That's all. There no need 4 wires connect in one time. Especially it's no need because if I connect 4 wires in one time motor will not spinning: first wires spin it clockwise second wires counterclockwise. But for work I should (I do) use driver. I have L293DNE. Can you tell me more about this type of motor? It's still call "stepper"?

Just forget about the behaviour with only one winding driven, its not useful, you need to
drive 4 wires. Many things do odd things if abused, seldom useful.