Grumpy_Mike:
It is AC, it doesn't have a polarity!With AC first one wire is positive and the other is negative, the in a 60th of a second (or so ) this is reversed. The change over from one state to the next is normally a smooth sinusoid.
yes it doesnt have polarity but.... i have made i small experiment, i just put upside-down the stator and as spected the motor changes from CW to CCW.... so, may be a posible way to change dir externaly or that what i think...