Page 443 - Basic Electrical Engineering
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Power factor
Total power, P = V I cos ϕ
L L
= × 400 × 23.1 × 0.8
= 12,800 W
Total volt amperes = V I
L L
= × 400 × 23.1 = 16,000VA
Example 4.3 A three-phase four-wire supply system has a line voltage of
400 V. Three non-inductive loads of 16 kW, 8 kW, and 12 kW are connected
between R, Y, and B phases and the neutral, respectively. Calculate the
current flowing through the neutral wire.
Solution:
Loads connected between the different phases and the neutral are of 16 kW, 8
kW, and 12 kW, respectively.
The current through the neutral wire line is the phasor sum of all the line
currents. We will first calculate the line currents and then add them
vectorially.
Figure 4.12
