Here in this poster can include questions to get the answer or the inclusion of questions to test everyone and make educational content more fun and useful.Wait for your participation with us.
I will Start put the first question

Q1/Why Does an AC Motor Need a Capacitor to Start?



 
You will find in this PPT all important and useful information for induction motors.
I want you to summarize some benefits from the PPT at lest one.
 
This technical manual for Three-Phase Induction Motors is the first publication of a series on the topic of "Motor Management".
With these published fundamentals the user will have a growing reference
work on the performance and operational data required for design and
application. The following topics will be covered:

• Starting and operating motors
• Protection of motors and drives
• Selection and operation of controls
• Communications

Electric motors can be found in almost every production process today.
Getting the most out of your application is becoming more and more 
important in order to ensure cost-effective operations. "Motor Management"
from Rockwell Automation will help you:

• to optimize the use of your systems
• to reduce maintenance costs
• to increase dependability

We are pleased that our publications may help you find economical and
efficient solutions for your applications.

Content:
Design
Duty Types
Selection
Dimensioning
Copyright © 1996 by Sprecher+Schuh AG Rockwell Automation, Aarau. 
All information supplied is accurate to the best of our knowledge and without legal liability.
 
Synchronous speed
The synchronous speed of an AC motor is the rotation rate of the rotating magnetic field created by the stator. It is always an integer fraction of the supply frequency. The synchronous speed ns in revolutions per minute (RPM) is given by:

where f is the frequency of the AC supply current in Hz and p is the number of magnetic pole pairs per phase. When using total number of poles, use 120 as constant instead of 60.;For example, a small 3-phase motor typically has six magnetic poles organized as three opposing pairs 120° apart, each powered by one phase of the supply current. So there is one pair of poles per phase, which means p = 1, and for a line frequency of 50 Hz the synchronous speed is 3000 RPM.
Slip
Typical torque curve as a function of slip (slip is represented by g here, which is proportional to s in the formula at left).
Slip s is the rotation rate of the magnetic field, relative to the rotor, divided by the absolute rotation rate of the stator magnetic field

where  is the rotor rotation speed in rpm. Slip is zero at synchronous speed and 1 (100%) when the rotor is stationary. The slip determines the motor's torque. Since the short-circuited rotor windings have small resistance, a small slip induces a large current in the rotor and produces large torque.At full rated load, typical values of slip are 4-6% for small motors and 1.5-2% for large motors, so induction motors have good speed regulation and are considered constant-speed motors

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    This blog include some info,video,books,PPT...all about induction motor.

     I hope you get benefits from our blog.

    Posts by: Abdullah 
    Al-ghamdi and Yazeed Alamri.

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