Motor Absorbed Power Calculator:
Enter the values of motor efficiency, n, applied voltage, V(V), current, I(A) and power factor, PF to determine the value of Motor absorbed power, Pa(W).
Motor Absorbed Power Formula:
Motor absorbed power (Pa) represents the rate at which an electric motor consumes electrical energy to perform mechanical work. This power consumption includes losses due to inefficiencies in the motor, such as heat, friction, and electrical resistance.
It is essential to determine the actual power absorbed by the motor to ensure proper sizing and efficient operation.
The efficiency of the motor, given as a percentage (%).The voltage supplied to the motor, measured in volts (V). The electrical current drawn by the motor, measured in amperes (A). The power factor of the motor, a dimensionless number between 0 and 1, indicating the phase difference between voltage and current.
Electrical energy from the source (voltage and current) is supplied to the motor. The motor’s internal components (magnets and windings) convert this electrical energy into mechanical work through the principles of electromagnetism.
However, some energy is lost as heat due to inherent inefficiencies within the motor (represented by 100 – n in the efficiency term).
Motor absorbed power, Pa(W) in watts is calculated by the product of motor efficiency, n in percentage, applied voltage, V(V) in volts, current, I(A) in amperes, power factor, PF and 0.017.
Motor absorbed power, Pa(W) = (n / 100) * 1.732 * V(V) * I(A) * PF
Pa(W) = motor absorbed power in watts, W.
n = motor efficiency in percentage.
V(V) = applied voltage in volts, V.
I(A) = current in amperes, A.
PF = power factor.
Motor Absorbed Power Calculation:
1. Finding Absorbed Power (Pa)
Given:
Efficiency, n = 90%
Voltage V(V) = 400 volts
Current I(A) = 10 amperes
Power Factor, PF = 0.85
Motor absorbed power, Pa(W) = (n / 100) * 1.732 * V(V) * I(A) * PF
Pa(W) = 0.90 * 1.732 * 400 * 10 * 0.85
Pa(W) = 5309W.
2. Finding Current (I)
Given:
Efficiency, n = 85%
Voltage V(V) = 380 volts
Motor absorbed power, Pa(W) = 6000W
Power Factor, PF = 0.9
Motor absorbed power, Pa(W) = (n / 100) * 1.732 * V(V) * I(A) * PF
I(A) = Pa(W) / (n / 100) * 1.732 * V(V) * PF
I(A) = 6000 / 0.85 * 1.732 * 380 * 0.9
I(A) = 6000 / 503.69
I(A) = 11.91A.