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I

106 ELECTRICAL APPARATUS

or negative, for-a low secondary resistance motor of impedance:

Z = 0.1 + 0.3;
and a high resistance armature, of the motor impedance :

Z = 0.3 + 0.1 j
resistance inserted into the one motor circuit, has the same effect

1.0

.8

.6

.4

^
Z =
3+lj
(Z«
= 14-3
f

a=

+.2
/
{/

4-8 4
7 4-
6 4
5 4
4 4
S 4
2 4
1
/^

Z=l
4-33
(/
= 34-:
3

r 4
2 4
3 4
4 4
5 4
6 4
7 4-8

/f
0
4-.2

Of
PAC
TV

/
/
+.4
IN
DUG'
PANC
E (F
ESIS
TAN
2E)

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•K6

^

^

+.8

-^
^^j
34-1*
^^^
' /

4-1:0

/

4-1.2

\

/

4-1.4

\

/

+1.6

\

/

4-1.8

\
<!
4-33
........ ar-*
X

4-2.0

1

FIG. 37.—Apparent starting-torque efficiencies of phase-splitting device,
parallel connection of motor circuits.
in the first motor, as positive reactance in the second motor, and
inversely.
69. Higher values of starting-torque efficiency are secured by
the use of capacity in the one, and inductance in the other motor
circuit. It is obvious that by resistance and inductance alone,
90° phase displacement between the two component currents,
and thus true quarter-phase relation, can not be reached.
As resistance consumes energy, the use of resistance is justified