Mechanical Systems 377
tor-run (or two-value capacitor) motor. Its circuit is shown in Figure 14-21.
This motor employs two capacitors. One, of low value, is in series with the
start winding and remains in the circuit during operation. The other, of
higher value, is in series with the start winding and a centrifugal switch.
The larger capacitor is used only to increase starting torque, and is re-
moved from the circuit during normal operation by the centrifugal switch.
The smaller capacitor, and the entire start winding, are part of the opera-
tional circuit of the motor. The smaller capacitor helps to produce a more
constant-running torque, as well as quieter operation and an improved
power factor.
Still another type of capacitor motor is one that is called a perma-Figure 14-19. The capacitor-start, single-phase induction motor: (A) Pictorial di-
agram, (B) Schematic diagram