SINGLE-PHASE INDUCTION MOTOR 111

and thus:

/ - €l62 s*n ^ -_______?i&

j ~~* o ~

(59)

and for maximum, Z:
thus:

(60)
or, substituting back:

/ ^. f ____&____- 0 18

wyj • & — >i /„ i a.\ — U. la.

As in single-phase operation, the voltage, e0, is impressed upon
the two quadrature coils in series, each coil receives only about

Comparing then the single-phase starting torque with that

of a quarter-phase motor of impressed voltage, ~-> it is: ;,
t = 0.36. I
The reader is advised to study the possibilities of capacity |
and reactance (inductive or capacity) shunting the two motor *
coils, the values giving maximum torque, those giving true |,
quarter-phase relation, and the torque and apparent torque J;
efficiencies secured thereby. " $•'
B. INDUCTIVE DEVICES f]
External Inductive Devices J
i
72. Inductively divided circuit: in its simplest form, as shown
diagrammatically in Fig. 39, the motor contains two circuits
at right angles, of the same admittance.
The one circuit (1) is in series with the one, the other (2) with
the other of two coils wound on the same magnetic circuit, M.
By proportioning the number of turns, n-i and n2, of the two coils,
which thus are interlinked inductively with each other on the
external magnetic circuit, M, a considerable phase displacement