Performance calculations on L- and T-connected tapped-winding capacitor motors

Although two-speed tapped-winding capacitor motors have been used for some forty years to drive shaft-mounted fans, the literature appears to lack information on their theory and how to calculate their performance characteristics. In this paper, the double-revolving-field theory, as developed by W. J. Morrill, is used as a basis for developing equations from which the total performance of such motors can be calculated over the entire speed range. These equations were programmed on a digital computer, and speed-torque curves were calculated and plotted for purposes of illustration.