Is a Unifilar stepper motor same as Bipolar stepper motor?

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I've a 2 phase 1.8 deg/step nema34 stepper motor and I'm a little confused as to how I get this thing to rotate in any direction. . .I've 4 wires with no common ground. . .I've been looking through google but I'm still uncertain as to whether I alternate Vdc between Vdc and ground or Vdc and -Vdc:
---------coil1------coil2
step1---vdc--------gnd
step2---gnd--------vdc

or if I'll need a negative supply to do the following

---------coil1------coil2
step1---vdc-------(-)vdc
step2-(-)vdc--------vdc

any insight would be much appreciated. . .

datasheet can be found here:http://www.kelinginc.net/KL34H280-60-4A.pdf

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In order to do this, usually one uses only one supply rail, and dual H-bridge circuits, like L293, NE754410, L289, etc. Take a look at their datasheet (L298D could be the first) and there you will find the thruth table and how it works.
More or less, you have to activate coils in one way, deactivate them, and then activate in the opposite way, alternating coils (remember that this motors have two coils, with two wires each).

Hope this helps.

Guillem.
"Common sense is the least common of the senses" Anonymous.

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Quote:
Is a Unifilar stepper motor same as Bipolar stepper motor?

No, there is a fundimental difference.

In the basic 6 wire 4 coil unipolar motor the windings are centertapped, with that connection going to one of the supply rails, usually the positive one. The remauning 4 coil ends are pulsed to the other supply rail, usually negative, in the correct sequence to rotate the motor, sometimes more than one coil is energised at one time.

With the 4 wire bipolar steppermotor, there is no centertap, which requires the two coils to be energised with a voltage which must alternate in polarity and be of the correct sequence, forcing you to use a H-Bridge, for each winding.

Thats the basics, the merit of either method is up to you to resolve.

The motor you have is more complex to drive than its 6 wire equivilent but not that hard if you can use the driver IC's like Guillem mentioned, but this depends on your voltage and current requirements.

Ron.

 

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Unifilar and bifilar is the coil winding technique.. one or two wires. Unipolar and bipolar is the power supply voltage. Unipolar voltage to the center tap lets you use 4 regular old switch to ground mosfets to drive the coils, but only half the coil is energized at a time. The H-bridge technique of driving one end up and the other end down lets you drive the coil either positive or negative with one power supply voltage. Clever, but more complicated in the hw. Also energizes the whole coil at one time.

Imagecraft compiler user

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So would it be accurate to descibe the motor I originally linked to as a bipolar,unifilar[ly?] wound motor?

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The only person who cares if it has 1 or 2 wires in the coil is the guy that winds it. It makes the center tap easy to find... its one end of the pair of wires.

Imagecraft compiler user