Power Factor Correction
Calculator
Results
- Capacitor bank size (kVAr)
- 55.323299
- Apparent power before correction (kVA)
- 133.333333
- Apparent power after correction (kVA)
- 105.263157
- Capacitance per phase (µF)
- 1,100.622079
Electrical results
| Capacitor bank size (kVAr) | 55.323299 |
| Apparent power before correction (kVA) | 133.333333 |
| Apparent power after correction (kVA) | 105.263157 |
| Capacitance per phase (µF) | 1,100.622079 |
formula-map diagram
- Capacitor bank size (kVAr)
- 55.323299
- Apparent power before correction (kVA)
- 133.333333
- Apparent power after correction (kVA)
- 105.263157
- Capacitance per phase (µF)
- 1,100.622079
Electrical relationship
Formula
Qc = P × (tan(arccos φ1) − tan(arccos φ2))= 55.323299850933
Note
This is a simplified model: it applies the textbook relationship to the numbers you entered and assumes ideal components, steady-state sinusoidal conditions, balanced loads and copper resistivity of 0.0172 Ω·mm²/m at 20 °C. It ignores component tolerances, temperature drift, skin effect, harmonics, inrush, transformer and battery losses, and it is not a substitute for the wiring code that applies where you are. Have any installation sized and verified by a licensed electrician or engineer.
More in Electrical engineering
See all →Frequently asked questions
What does power factor actually measure?+
Power factor is the ratio of real power (the power that does useful work, in watts) to apparent power (volts x amps supplied by the source). A power factor of 1 means all the supplied power is being used productively; anything less means some power is flowing back and forth without doing work.
Why does a low power factor cost money even if it doesn't waste energy?+
Utilities and wiring have to be sized for the higher apparent current a low power factor demands, even though the reactive portion isn't consumed. Many commercial and industrial electricity rates include penalties specifically for poor power factor.
How does adding a capacitor correct power factor?+
Most industrial loads (motors, transformers) are inductive, drawing lagging current; a capacitor bank supplies leading reactive current that cancels out the inductive component, bringing the overall current closer in phase with the voltage.
What size of capacitor is needed for a given correction target?+
The required reactive power (in kVAR) is calculated from the difference between the reactive power at your current power factor and the reactive power at your target power factor, then converted to a capacitance value at your supply frequency and voltage.
Can you over-correct power factor?+
Yes, adding too much capacitance flips the load from lagging (inductive) to leading (capacitive), which can also cause utility penalties and, in more severe cases, voltage rise or resonance issues — the goal is usually to correct to around 0.95-1.0, not necessarily to exactly 1.0.