Stepper question

[DexterLB]

I have an unipolar stepper motor.
There is a possibility not to use the common wires and use it as a bipolar motor. Will I benifit from that? Will I get more torque?
Of course, if I do that the circuit will be far more complex, but I don't care about that. So, do I get more torque, or more power if I use it as a bipolar?

 

[shortbus=]

HI, alot of good stepper information here; Jones on Stepping Motors

 

[DexterLB]

I guess there will be less heating if I use the bipolar method as I am spreading the same amount of current on a longer wire (e.g. the entire coil). I'll make two test boards one for the unipolar method and one for the bipolar and see if there's any difference. Thanks for the help anyway.

 

[mneary]

What's to vote on? A stepper doesn't change by consensus. It is what it is.

 

[Sceadwian]

Not true mneary, some (all?) 6 wire unipolar steppers can be wired as bipolar.

 

[DexterLB]

5 wire too.
But the question is: To Be, or not to Be?

 

[Sceadwian]

As long as the current is the same the torque should be the same, you're not inherantly changing anything about the motor just the way it's driven.

 

[mneary]

When a six-wire stepper is wired as bipolar, each pair of windings becomes one series inductor with twice as many turns, twice the DC resistance, and 4X the inductance. At the original voltage each winding will get half the current, but since there are twice the turns the torque will be the same. Sounds like something for nothing, but you pay the price in speed, as the current takes longer to build due to the added inductance.

 

[arunb]

I use unipolar stepper motors all the time, I use a SLA 7062M translator device with these steppers, I find these very efficient.

The motors do not get hot even after extensive use.....

thanks
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