Engineering Board Exam Reviewer · RLC Circuits and Resonance · hard
A 6 kW load has a power factor of 0.75 lagging. How many kvar of parallel capacitance raise the power factor to 0.95 lagging?
- 5.29 kvar
- 7.26 kvar
- 2.68 kvar
- 3.32 kvar
Answer
D. 3.32 kvar
Solution
Initially Q1=P ( -10.75)=6000(0.8819)=5291 var. After correction Q2=P ( -10.95)=6000(0.3287)=1972 var. QC=Q1-Q2=3.32 kvar.
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