Single Phase Power Equations

Power equations for single phased electrical systems. Calculate real power, total power, and brake horsepower.

Single Phase Power Equations

Power equations for single phased electrical systems.

Real Power

Wapplied = U × I × PF / 1000

where:

  • Wapplied = real power (kilowatts, kW)
  • U = voltage (volts, V)
  • I = current (amps, A)
  • PF = power factor (0.7 - 1.0)

Total Power

W = U × I / 1000

where:

  • W = total power (kilowatts, kW)
  • U = voltage (volts, V)
  • I = current (amps, A)

Brake Horsepower

WBHP = U × I × PF × μ / 746

where:

  • WBHP = brake horsepower (hp)
  • U = voltage (volts, V)
  • I = current (amps, A)
  • PF = power factor (0.7 - 1.0)
  • μ = device efficiency (0 - 1.0)
Calculator

Inputs

Results

Real Power (Wapplied)-- kW
Total Power (W)-- kW
Brake Horsepower (WBHP)-- hp
ParameterSymbolUnitDescription
VoltageUVElectrical potential difference
CurrentIAElectrical current flow
Power FactorPF-Ratio of real power to apparent power (0.7 - 1.0)
Efficiencyμ-Device efficiency ratio (0 - 1.0)
Real PowerWappliedkWActual power consumed or delivered
Total PowerWkWTotal apparent power
Brake HorsepowerWBHPhpActual power delivered to or by a shaft