# How do I find motor rating?

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Multiply the motor voltage by the full-load current. The result is in watts. Divide watts by 1,000 to give kilowatts. For example, 230 volts x 20 amps = 4,600 watts; 4,600 watts divided by 1000 = 4.6 kilowatts.

## How do you find the power rating of a motor?

For a DC source the calculation is simply the voltage times the current: W = V x A. However, determining the power in watts for an AC source must include the power factor (PF), so W = V x A x PF for AC systems.

## How do you check motor rating without nameplate?

If there is no name plate, you won’t be able to know the rated voltage too. In that case, you may have to guess the approx. HP depending upon the size of the motor, select appropriate auto transformer and then run at no load by slowly increasing the voltage till it reaches steady state.

## How are motors rated?

Electrical motors are rated in horsepower or watt

The unit of electric power – 1 watt – is equal to the power produced by an electrical current of 1 amp at a potential difference of 1 volt.

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## How many amps is 3 horsepower?

Common Horsepower to Amps Conversions

Horsepower Amps Voltage
3 HP 20.7 A 120 V
3.5 HP 24.2 A 120 V
4 HP 27.6 A 120 V
4.5 HP 31.1 A 120 V

## How many watts is a 1 hp motor?

One electric horsepower is equal to exactly 746 watts.

## What does engine number tell you?

Automobiles. Every vehicle engine is marked with an engine number by the factory. The engine number includes coded information, which can be decoded to reveal, for example, year of manufacture, country of manufacture, and engine type.

## How do I find my engine number?

The engine number is found on the body of the car’s engine. Car manufacturers ensure that the number is clearly visible. It is imprinted on a metal sticker and placed in such a way that it is easy to see when you open the hood.

## How do you know the number of poles in a motor?

To determine the number of poles, you can read the data plate directly or calculate it from the RPM stated on the data plate or you can count the coils and divide by 3 (poles per phase) or by 6 (pairs of poles per phase).

## What information is on a motor nameplate?

Nameplate-defined parameters for the motor such as power factor, efficiency, torque, and current are at rated voltage and frequency. Application at other than nameplate voltage will likely produce different performance. It is common for manufacturers to nameplate a wide variety of voltages on one motor nameplate.

## What is rated power of motor?

Rated power is the power which a machine or device can deliver under design voltage and frequency conditions. In an electrical machine or motor , this means the physical power which can be delivered under these conditions. … The power of any LOAD device is the product of its input voltage and its current consumption.

## What is short time rating of motor?

A short time rating of an electric motor can be defined as the extrapolated overload rating of the motor which it can supply for the specified short time without getting overheated. Now a days the machines are being designed and manufactured for short duration having sufficient overload torque capability.

## What is rated current of motor?

The rated current (or nominal current) is the current the device is rated at for continuous service. … and Full load current is the current when the motor is subjected to the load that it can bear and the current at that time is called full load current. 