Answer / ankush miglani 09718151073

in induction motor power is not fed to rotor but it is
induced in the rotor through electromagnetic induction.
its various starting methods are:
1. dol direct on line starting
2. star delta starter
3. through variable frequency drives
4. restance starter
5. auto transformer starter
6. series reactor starter

Answer / virendra joshi

Yes, as armine said that there is a diffrent method for
starting both the motores in single phase more it can be
driven as capacitor start, capccitor run ,also capacitor
start capacitor run motor.

Considering a three phase motor when three phase supply is
given to the startor winding rotating magnatic field is
developed which rotaes with syschronous speed ( NS =
120F/P ). now this magnatic field is connected to rotar bar
& as the rotar winding is shot ( in case of Squrell cage
rotor through copper ring & in case of sleepring rotor
through resistence ) so the current flows in rotor bar .
now as this in magnatic field . the force is applied on the
rotor . rotor start moving & as the magnatic field is
rotating rotor keep moving but is legs behind a bit then a
synchronous speed & this phenomina called a Slip.

please revert if any querry exists.

Answer / armine george

please specify whether its a single or three phase motor.
becoz both of them hav different starting methods

Answer / amjad ali soomro

The stator Like A primary and Rotor Acts as a secondary ,
When stator is powered by the primary the squirrel cage rotor .The substantial iron cores, with a very small air gap between stator core and rotor core, efficiently conveys the magnetic fields produced by the stator currents to the rotor conductors. A stator (primary) sine wave voltage will induce a sine wave voltage in the rotor (secondary), the same as any transformer. But the rotor will have no overall force acting on it to cause rotation. If its is 3-Phase than it will Automatically starts Revolving field developed by three phases
and if it is single phase than it will require external rotation...

why insulators colour is BROWN?

1 Answers  

---

what is diff kav & kvarh?

3 Answers  

---

difference between isolater and circuit breaker?

7 Answers   Adani,

---

how we calculate the 30 KW 3phase electric motor current on noload

23 Answers   Monnet, Siemens, SSR, Supermac Industries,

---

Why is transformer a machine

1 Answers   Grasim,

---

what is interpose vt where it is used and y it is used?

0 Answers  

---

Weather power factor correction needed for synchronous motors?

1 Answers  

---

need of capacitor used in plant

3 Answers  

---

why induction motor takes high current?

1 Answers   Emerson,

---

why are laminations used in constructing the field core?

3 Answers  

---

how to estimate wiring ins roughing ins. and boxes

0 Answers  

---

why firewall is build up between two transformer (220/11kv,50MVA)?what should be the firewall height?what is the clearance between firewall and transformer?

2 Answers   Siemens, Tous Stadt,

---