Power Factor Calculator
Power Factor is evaluated from Real Power, Apparent Power and Power Factor. The calculation reports Power Factor, Phase Angle and Real Power.
Results
About the Power Factor Calculator
The calculator uses a multi formula configuration. Each reported value is read as a direct evaluation of the stored rules with the declared field formats and units.
Formula basis:
PF = P / S = cos(φ)
P = S x PF (Real Power in kW)
S = P / PF (Apparent Power in kVA)
Q = sqrt(S^2 - P^2) (Reactive Power in kVAR)
From V and I: S = V x I / 1000 (kVA)
Phase angle: φ = arccos(PF) in degrees
Interpret the outputs in the order shown by the result fields. Optional inputs affect only the outputs that depend on those variables.
Formula & How It Works
The calculation applies the following relations exactly as recorded in the metadata: PF = P / S = cos(φ) P = S x PF (Real Power in kW) S = P / PF (Apparent Power in kVA) Q = sqrt(S^2 - P^2) (Reactive Power in kVAR) From V and I: S = V x I / 1000 (kVA) Phase angle: φ = arccos(PF) in degrees Each output field is produced by substituting the supplied inputs into the relevant relation and then applying the declared rounding or text format.
Worked Examples
Example 1: Industrial Motor — PF Correction
Inputs
With Real Power = 50 and Apparent Power = 62.5 as the stated inputs, the result is Power Factor = 0.8, Phase Angle = 36.87 deg and Real Power = 50 kW. Each value corresponds to the declared output fields.
Example 2: Residential HVAC Unit
Inputs
With Power Factor = 0.92, Line Voltage = 240 and Line Current = 20 as the stated inputs, the result is Power Factor = 0.92, Phase Angle = 23.07 deg and Real Power = 4.416 kW. Each value corresponds to the declared output fields.
Example 3: Unity Power Factor Check — Resistive Load
Inputs
With Real Power = 3 and Apparent Power = 3 as the stated inputs, the result is Power Factor = 1, Phase Angle = 0 deg and Real Power = 3 kW. Each value corresponds to the declared output fields.
Example 4: Data Center UPS Sizing
Inputs
With Real Power = 800 and Power Factor = 0.9 as the stated inputs, the result is Power Factor = 0.9, Phase Angle = 25.84 deg and Real Power = 800 kW. Each value corresponds to the declared output fields.
Common Use Cases
- Find power factor correction capacitor size for an inductive motor
- Calculate real power from kVA rating and power factor
- Determine reactive power (kVAR) drawn by equipment