# Electric Motors

 Hi... I need to know about the efficiency of 3 phase electric motor where i have only input voltage,current,frequency & rpm. What is the formula to find the efficiency? asked 12/14/2016 Manick2

 i think by using the relation of the losses so we can find the losses and subtract the losses we get output .i think it is correct .we can get an appropriate efficiency. if wrong forgive me sir .and please tell me the solution sir.thank you answered 12/30/2016 Thulasi 2 E(efficiency) Po(power out) Pi(power in) E=Po/Pi thus, if you have the rating of the power delivered you just divide it and get your efficiency  OR can use the following  E=(746*HP)/[(746*HP)+(watts lost)] Where 746 is a constant and HP=horsepower just my two humble cents, hope this helps Regards answered 9/21/2018 Expeditions Conquistador 2 an electric motor is an electrical machine thats convert electrical energy to mechanical energy most electric motors  operate through the interaction between the motors magnetic field and winding currents to generate force in the form of rotation answered 2 months ago rajkishor 2

In order to provide an answer to this question, you must Login

## I am flagging this question because...

10 inform moderator flags remaining

## I am flagging this answer because...

10 inform moderator flags remaining

## Flagging a Post

You have already flagged this post. Clicking "Remove Flag" below will remove your flag, thus reducing the count by one as well.

## I am deleting this answer because...

Restricted Earth Fault Protection

The windings of many medium and small sized transformers are protected by restricted earth fault (REF) systems. The illustration shows the principal of...

Motor Insulation

Insulation on a motor prevents interconnection of windings and the winding to earth.  When looking at motors, it is important to understand how the insulation...

Fault Calculation - Per Unit System

Per unit fault calculations is a method whereby system impedances and quantities are normalised across different voltage levels to a common base.  By removing...

Differential protection, the good old days

This morning I was explaining how differential protection works to a junior engineer. To give him something to read I opened up the NPAG (Network Protection...

Motor Starting - Introduction

Motor starting and its associated problems are well-known to many people who have worked on large industrial processes. However, these things are, of course...

8 Steps to Low Voltage Power Cable Selection and Sizing

A recurring theme on our forums is cable sizing. Now many installations are unique and require special consideration. However, a lot of the time things...

Smarter Electrical Distribution

The other day I came across an article in Technology Review on the development of a smart transformer. A professor at North Carolina State University is...

Introduction to Lighting

When looking at the design of a lighting scheme it is useful to have an understanding on the nature of light itself and some of the basic theory associated...

Autonomous Vehicle Challenge

Two driverless and solar power vans have departed from Italy on their way to China via the silk road. During the 13,000 kM trip the vans will drive themselves...

How to Write an Electrical Note

Electrical notes are a collaborative collection of electrical engineering information and educational material. Any registered user can add content. ...

Our website uses cookies so that we can provide a better experience.