# Frequent question: How do you find the input power of a motor?

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By taking the voltage and multiplying it by the associated current, the power can be determined. A watt (W) is a unit of power defined as one Joule per second. For a dc source the calculation is simply the voltage times the current: W = V x A.

## How do you calculate the input power of an induction motor?

It could be also converted further to still common gram force centimeters (g-cm) by multiplying the result by 10.2, i.e. the torque is 12.86 g-cm. In our example input electrical power of the motor is 0.22 A x 6 V = 1.32 W, output mechanical power is 1000 rpm x 2 x 3.14 x 0.00126 N•m /60 = 0.132 W.

## What is input power of motor?

Motor Input Power is the electrical power supplied at the terminals of an electric motor drive. The difference between Motor Input Power and Fan Input Power (Absorbed Power) is a measure of the losses both mechanical and electrical within the motor.

## How do you calculate input power?

Input and output power

1. Electrical power is calculated by multiplying voltage (in volts) by current (in amps).
2. If a transformer is 100% efficient, then the input power will equal the output power. …
3. V P is input (primary) voltage.
4. I p is input (primary) current.
5. V s is output (secondary) voltage.

## How do you calculate the input power of a single phase induction motor?

AC single phase motor power calculation:

P(W) = V(V) x I(A) x pf.

## How do you calculate the input power of a 3 phase induction motor?

Calculate three-phase motor power consumption by multiplying amps by volts by the square root of three (W = AV(sqrt 3). For example, if the motor is drawing 30 amps at 250 volts, you have 30 x 250 x sqrt 3 (about 1.73) = 12,975 watts).

## What is the input power?

Input power is the power that is fed into a machine, say for instance, Mechanical power input through a prime mover in case of alternators, or electrical input in case of motors. Now, Rated input power is the maximum input power that can be fed to the machine for safe operation.

## How do you calculate input power efficiency?

We can calculate the efficiency of anything by dividing the energy input and the energy output by 100%. We use this equation generally to represent the energy in the form of heat or power.

## How do you find the input power of a circuit?

Power Measurement Basics

DC power measurement is relatively simple as the equation is simply watts = volts x amps. For AC power measurement, the power factor (PF) introduces complexity as watts = volts x amps x PF. This measurement of AC power is referred to as active power, true power or real power.

## Is motor rated input or output power?

For an electrically driven motor, the output power is mechanical while the input power is electrical, so the efficiency equation becomes efficiency = mechanical power/electrical input power.

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## How do you calculate power in a single phase motor?

I use the simple, single-phase calculation. However, although there are only two wires, the phase angle between the two legs on the primary is 120 degrees, not 180 degrees.

## How do you calculate the power factor of a single phase motor?

Single phase power equations:

1. Real Power. Wapplied = U I PF / 1000 (1) where. Wapplied = real power (kilowatts, kW) U = voltage (volts, V) I = current (amps, A) PF = power factor – 0.7 – 0.95.
2. Total Power. W = U I / 1000 (2)
3. Brake Horsepower. WBHP = U I PF μ / 746 (3) where. WBHP = brake horsepower (hp) μ = device efficiency.