Capacitor kVAR Calculator
Estimate the capacitance required for a three-phase capacitor bank when reactive-power target, line voltage, system frequency and connection are known. This is useful for preliminary power-factor correction studies.
Preliminary sinusoidal calculation only. Harmonics, resonance, tolerances, switching duties and equipment voltage ratings require engineering review.
How this tool works
For wye, total Q = VLL² × 2πf × C per phase. For delta, total Q = 3 × VLL² × 2πf × C per phase. Solve these expressions for C.
Example
At 480 V and 60 Hz, a 50 kVAR bank requires different per-phase capacitance depending on whether the capacitors are connected wye or delta.
Common questions
Can I use this to select a production capacitor bank?
Use it as a preliminary calculation only. Harmonics, resonance, switching transients, tolerances and equipment ratings require engineering review.
Why does wye need more capacitance per phase than delta?
Each wye capacitor sees phase voltage rather than full line-to-line voltage, so more capacitance is required for the same total kVAR.