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In: Electrical Engineering

Three loads are connected in parallel to an AC supply of 120∠0° V. The loads are...

Three loads are connected in parallel to an AC supply of 120∠0° V. The loads are 40∠30° Ω, 50 - j30 Ω
and 30 + j40 Ω.
a) Draw the circuit diagram
b) Determine the amplitude and phase angle of the supply current graphically by constructing a
phasor diagram using a suitable scale of the load currents and source voltage.
c) State the overall power factor using the answer from part (b).
d) Construct another phasor diagram for the system that illustrates an improved power factor to
unity.
e) Determine the VAR rating of the load required to achieve this using its current phasor determined
graphically from part (d). State its capacitance or inductance.
f) Draw the power triangles for the system before and after power factor correction.

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