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Ralph Mowery

In article ,
says...

There is no charge to make a surge. It works by creating a phase
shift, which is necessary to get the motor rotating. Where is
this alleged surge coming from? The start cap has no power to it

Oh, but there is.. The start capacitor is energized and patiently waits
to be tied into the compressor motor, usually on the start windings.

This is why hvac techs always drain capacitors when they encounter
them. Only an idiot would assume a capacitor isn't storing a charge and
proceed to screw around with things connected to it. Especially if the
device it's connected to has been powered up (or tried to power up)
recently.

The capacitors are not sitting there with a charge on them waiting to
dump it to start the motor. The only reason they may or may not be
charged is that the alternating current goes from 0 to the peak voltage
during the cycle. Depending on where in the cycle the relay or other
set of contacts open the voltage left on the capacitor could be anywhere
from the peak negative to the peak positive voltage.

The purpose is to provide a phase shift, not hold any charge to provide
a bost.

Just trying to asume that what you say is correct, explain how if the
charge on the capacitor is the wrong polarity (as they can only store
DC) that the voltage would buck the alternating current and the motor
would not start correctly.

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