Power Factor Calculator

⚡ Power Factor Calculator

Calculate power factor, apparent power, reactive power and correction capacitor's capacitance

This calculator is for educational purposes.

kW
A
V
Hz

📊 Calculation Results

Power Factor Result
-
Apparent Power
- kVA
Reactive Power
- kVAR
Correction Capacitor
- μF
📝 Example Calculation
Problem: A single-phase motor draws 15 A current at 240 V with a power factor of 0.8. Calculate the apparent power, reactive power, and capacitor needed to improve power factor to 0.95.

Given:
• Current (I) = 15 A
• Voltage (V) = 240 V
• Power Factor (cos φ₁) = 0.8
• Desired Power Factor (cos φ₂) = 0.95
• Frequency = 60 Hz

Solution:
• Real Power (P) = V × I × cos φ = 240 × 15 × 0.8 = 2.88 kW
• Apparent Power (S) = V × I = 240 × 15 = 3.6 kVA
• Reactive Power (Q) = √(S² - P²) = √(3.6² - 2.88²) = 2.16 kVAR
• Capacitor = 1000 × Q / (2π × f × V²) = 59.7 μF
🔬 Formulas Used

Single Phase Calculations:

Power Factor: PF = cos φ = P(kW) × 1000 / (V(V) × I(A))
Apparent Power: S(kVA) = V(V) × I(A) / 1000
Reactive Power: Q(kVAR) = √(S(kVA)² - P(kW)²)
Capacitor: C(μF) = 1000 × Q(kVAR) / (2π × f(Hz) × V(V)²)

Three Phase Calculations:

Power Factor: PF = cos φ = P(kW) × 1000 / (√3 × V(L-L) × I(A))
Apparent Power: S(kVA) = √3 × V(L-L) × I(A) / 1000
Reactive Power: Q(kVAR) = √(S(kVA)² - P(kW)²)
Capacitor: C(μF) = 1000 × Q(kVAR) / (2π × f(Hz) × V(L-L)²)

FAQS

Power Factor Formula?

Power factor = kW ÷ kVA or PF = cos(θ) where θ is the phase angle between voltage and current. Power factor measures electrical efficiency by comparing real power (kW) to apparent power (kVA), with values ranging from 0 to 1.

For 3-phase systems: PF = P ÷ (√3 × V × I × cos(θ)) where P is total power in watts, V is line voltage, and I is line current. Three-phase power factor calculation requires measuring all three phases and averaging the results for accurate system efficiency assessment.

PF = kW ÷ √(kW² + kVAR²) where kW is real power and kVAR is reactive power. To find missing values: kVA = √(kW² + kVAR²) and kVAR = kW × tan(θ) for complete power triangle calculations.

Power Factor = Real Power (Watts) ÷ Apparent Power (VA) expressed as PF = P/S. For single-phase AC circuits, measure actual watts consumed and divide by the product of voltage and current (VA) to determine power factor efficiency.

Standard Power Factor Values: Unity PF = 1.0 (100% efficient), Good PF = 0.95-0.99, Average PF = 0.80-0.95, Poor PF = below 0.80. Industrial facilities typically maintain 0.85-0.95 PF, while residential loads average 0.70-0.85 power factor.

Mobile apps and online calculators provide instant PF calculations using kW, kVA, kVAR inputs with built-in power triangle diagrams. Professional electrical apps include advanced features like harmonic analysis, cost calculations, and capacitor sizing for power factor correction.

Power Factor Calculation Formula in Excel?

Excel Formula: =B2/C2 where B2 contains kW (real power) and C2 contains kVA (apparent power). Advanced Excel calculations: =COS(RADIANS(D2)) where D2 is phase angle in degrees, or =B2/SQRT(B2^2+E2^2) for kW/kVAR method.

IPSC Power Factor = (Bullet Weight in grains × Velocity in fps) ÷ 1000. Major power factor requires minimum 165, while Minor power factor needs minimum 125 for competitive shooting classifications and scoring divisions.

Step 1: Measure real power (kW) and apparent power (kVA), then Step 2: Divide kW by kVA (PF = kW/kVA). Alternatively, use cos(θ) method by measuring phase angle between voltage and current waveforms for precise power factor determination.

Power factor depends on reactive power (kVAR) present in the system, not just real power (kW). 1 kW with 0 kVAR = PF of 1.0, while 1 kW with 0.75 kVAR = PF of 0.8, demonstrating that kW alone cannot determine power factor.

Use the formula PF = Real Power ÷ Apparent Power or measure with a power factor meter for direct readings. Digital multimeters with PF function provide instant measurements, while manual calculations require accurate voltage, current, and power measurements for reliable results.

Three-phase power factor ranges from 0.80-0.95 in typical industrial applications with balanced loads achieving higher efficiency. Unbalanced three-phase systems require individual phase measurements and vector calculations to determine overall system power factor and identify correction needs.