Single phase power equations:
Wapplied = U I PF / 1000 (1)
Wapplied = real power (kilowatts, kW)
U = voltage (volts, V)
I = current (amps, A)
PF = power factor - 0.7 - 1
W = U I / 1000 (2)
- Brake horsepower is the actual power delivered to or by a shaft.
WBHP = U I PF μ / 746 (3)
WBHP = brake horsepower (hp)
μ = device efficiency
Example - Horsepower vs. Current and Voltage
An AC motor consumes 8 amps of current. The voltage supplied is 12 V, the efficiency of the system is 96% (0.96) and the power factor is 1. The horsepower can then be calculated as
WBHP = (12 V) (8 A) (1) (0.97) / 746
= 0.125 HP
≈ 1/8 HP
Electrical units, amps and electrical wiring, wire gauge and AWG, electrical formulas and motors.
Real, imaginary and apparent power in AC circuits.
Characteristics of all-aluminum conductors (AAC).
Convert between single phase (120, 240 and 480 Voltage) and three phase (240 and 480 Voltage).
Calculate amps, hp and kVA for electrical motors.
Calculate electric motor efficiency.
Commonly used electrical formulas like Ohms Law and more.
Calculate electric motors shaft power.
EV Charging - AC vs. DC, single phase vs. three phase and power vs. voltage and amps.
Power is the rate at which work is done or energy converted.
Color codes used in power wiring.
Full load amps, wire and conduit sizes for three phase electrical motors.
Inductive loads and power factors with electrical three-phase motors.
Electrical 3-phase equations.