Single-Phase Two-Valued Capacitor Motor Relay Selection

The problems presented by an undesirably steep speedversus phasewinding voltage curve for a single-phase capacitor-start capacitor-run induction motor are discussed. A method of calculating the voltage across the phase winding as a function of speed is given along with a brief flow diagram for a digital computer program for calculating this voltage. Experimental and calculated curves are given. Emphasis is placed on methods for correcting an undesirable speed-phase-winding voltage relationship.