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    Reactive Components (C / L) — Capacitors & Reactors

    Convert capacitor-bank or reactor kvar to C/L, calculate delta/star branch values, and estimate kvar from isolated L-L measurements.

    Before you calculate

    Capacitance, inductance and kvar

    Choose Capacitive (C) or Inductive (L). Convert between nameplate kvar and equivalent terminal measurements, or enter isolated L-L readings to estimate reactive power. Ideal balanced-network assumptions apply.

    Learn more — illustrated guide →
    Step 1 · Component

    Capacitive or inductive?

    Capacitor-bank capacitance and capacitive kvar — including L-L field measurements.

    Step 2 · Known values
    Positive kvar magnitude. The component type determines capacitive or inductive sign.

    Important: measure only after isolation, discharge (capacitors), lockout, and verification of a safe de-energized state. Disconnect external components. Detuned banks, internal series/parallel units, discharge networks and coupled inductors need their own test method.

    Step 3

    Calculated results

    Expected L-L capacitance288.47 µFThree-phase · Delta · Capacitive (−Q)
    Reactive power magnitude29 kvar
    L-L terminal equivalent288.47 µF
    Individual branch value192.31 µF
    Line current41.86 A
    Branch reactance magnitude16.55 Ω

    Nominal calculation at the entered voltage and frequency, without resistive losses or external reactors.

    Step 4

    Step-by-step mathematics

    1. Convert the rating to a terminal measurement

    Calculate the expected line-to-line reading with the third phase left floating.

    CLL=Q×10002ωULL2C_{LL}=\frac{Q\times1000}{2\omega U_{LL}^{2}}
    CLL=29 × 10002 × 314.159 × 4002×106≈288.468 μFC_{LL}=\frac{29\,\times\,1000}{2\,\times\,314.159\,\times\,400^{2}}\times10^{6}\approx288.468\,\mu\mathrm{F}

    2. Derive the actual delta branch value

    The meter sees one capacitor in parallel with the other two in series.

    CLL=32CΔC_{LL}=\frac32 C_\Delta
    CΔ=23 × 288.468≈192.312 μFC_\Delta=\frac23\,\times\,288.468\approx192.312\,\mathrm{\mu F}

    3. Calculate reactance and line current

    This is the ideal reactive component only; real resistance, loss and harmonic behaviour require a separate analysis.

    XC=1ωCI=Q×10003 ULLX_C=\frac{1}{\omega C}\qquad I=\frac{Q\times1000}{\sqrt3\,U_{LL}}
    XC≈16.552 ΩI≈41.858 AX_C\approx16.552\,\Omega\qquad I\approx41.858\,\mathrm A

    Calculations use full numerical precision; only displayed values are rounded.