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HVAC Capacitors Explained

This is my attempt to explain HVAC capacitors, both run and start. I did some research on capacitors so I just want to get what I learned recorded. Difference between a current relay and a potential relay: ---------------------------------------------------------------------------- A "current" relay has a coil of low resistance wire (heavy gauge wire, few turns), and is energized only by a large current, such as the initial current of a motor starting. The relay coil is wired in series with the run/main winding of the motor, and the relay contacts are normally open. As the motor tries to start, the large current closes the relay, which momentarily brings the start/aux winding into circuit, allowing the motor to go. Used for split-phase and capacitor-start motors. A "potential" relay has a coil of high resistance wire (light wire, many turns), and is wired in parallel with the start/aux winding, and the relay contacts are normally closed. At initial motor start-up, high current will flow through both the run and start windings of the motor. As the motor reaches operating speed, the current reduces, and a "back EMF" is produced allowing current to now pass through the potential relay coil, and open the contacts. Used for capacitor-start and cap-start cap-run motors.