# Understanding motor rotation

Discussion in 'General Electronics Chat' started by CktMeister, Jun 8, 2011.

1. ### CktMeister Thread Starter New Member

Jun 8, 2011
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0
I am having a problem understanding motor rotation reversal. According to the all about circuits tutorial, swapping any two phases on a three phase motor causes it to reverse direction. I understand how the magnetic fields change so that by the left hand rule the magnetic fields vary in such a way that they either push or pull the rotor in one direction or other.

My problem is the following:

According the rule that swapping any two phases on a motor causes it to reverse direction, if I build a motor whose windings are configured to run clockwise when I apply 123 phased power, then it will run counter-clockwise when I apply 213, 321, or 132 power.

So haven't I also designed a motor that runs counter clockwise when I apply 321 power?

So then by "the swap any two phase rule", the motor should run clockwise when I apply 123,231,or 312.

And so if you swap three phases, or any two phases twice, you maintain the same direction-three ways for the motor to run clockwise and three ways counter clockwise?

Oct 3, 2010
4,302
1,989
correct

correct

correct

correct

3. ### CktMeister Thread Starter New Member

Jun 8, 2011
2
0
Thanks for the sanity check Strantor.