Run cap

Am I right in saying that the run cap in a single phase compressor helps in keeping the current and voltage more in phase with each other. Or is it so that the magnetic field of the stator is different from the magnetic field of the rotor.

the run cap provides a shifted phase for the auxilary winding, which results in good torque qualities as well as quiet/smooth operation.

GetDeviceInfo said:

the run cap provides a shifted phase for the auxilary winding, which results in good torque qualities as well as quiet/smooth operation.

Click to expand...

What do you mean by phase shift

forgive the filthy scope, or should I say philthy scope?

first photo shows two waves (channels a and b) in sync from same point at function generator input.
second photo shows the two channels superimposed from same point at function generator input.
third photo shows 90 degree phase shift after adding capacitor-resistor circuit to channel b input.
fourth photo shows a near 90 degree X-Y output.

now imagine a motor getting this second kick of energy.
you can imagine the benefits of a run capacitor.

http://forum.allaboutcircuits.com/showthread.php?t=32382