# Thread: PMinMo L297-8, Out1 & Out2 and stepper motor polarity

1. ## PMinMo L297-8, Out1 & Out2 and stepper motor polarity

Hi all,

Manage to have the 3 x L297-8 drivers and "DIY 4 Axis PC interface" works without much problem except I burned one 7805 and one stepper motor(Vref too high). I am glad that all 3 axis worked with the 6 wire bipolar motor with my try and error method.

I am curious about certain thing.

1. Which output is for A+ A- B+ B-?
Out1= X3-1, X3-2
Out2= X2-1, X2-1

2. As for stepper motor, I have 6 wires stepper (unipolar and bipolar).
I managed to determine those 6 wires
example
1, 2, 3 group A, A2=common
4, 5, 6 group B, B5=common

How to determine the polarity A1 & A3 and B4 & B6 which wire is + and -?

TIA and cheers
KC

2. http://techref.massmind.org/techref/...pper/wires.htm will help you find which wires are which on the motor.

http://techref.massmind.org/techref/...onnections.htm the table below the graph will give you the options for how to connect the stepper to the driver. In your case, with the 6 wire motor and a bi-polar driver: The common A and common B are held apart and not connected to anything. A+,A-,B+,B- to bipolar driver with 41% higher voltage than the motor rating.

As to the polarity, I don't have a lot of experience with Bi-polar motors, but I believe it's the same as for unipolar motors: Just hook up the controller A+, A-, B+, and B- terminals to the phase leads (guess at the phases) and try to step slowly.

If the motor does not turn, try swapping one A wire with one B wire, you may have connected the motor phasing wrong. If you have the phasing wrong, the motor will tend to sit there and "wobble" or "buzz".

If the motor turns, but in the wrong direction, you only need to swap the two A wires with each other.

3. Hi James,

That the method I had been doing for getting the bipolar stepper to turn correctly.
As for the L297-8, I am trying to find out, wasn't documented, Out1 and Out2 polarity.

Well, have a good day.