Answer / partha podder

Starting current of a motor is high.The simplest way to
start a three-phase induction motor is to connect its
terminals to the line. In an induction motor, the magnitude
of the induced EMF in the rotor circuit is proportional to
the stator field and the slip speed (the difference between
synchronous and rotor speeds) of the motor, and the rotor
current depends on this EMF. When the motor is started, the
slip speed is equal to the synchronous speed, as the rotor
speed is zero (slip equal to 1), so the induced EMF in the
rotor is large. As a result, a very high current flows
through the rotor. This is similar to a transformer with the
secondary coil short circuited, which causes the primary
coil to draw a high current from the mains. When an
induction motor starts DOL, a very high current is drawn by
the stator, on the order of 5 to 9 times the full load
current. This high current can, in some motors, damage the
windings; in addition, because it causes heavy line voltage
drop, other appliances connected to the same line may be
affected by the voltage fluctuation. To avoid such effects,
several other strategies are employed for starting motors.

Answer / mahesh chaudhari

Generally its 5 to 6 times than that of rated specified
current on motor name plate.

Answer / simon

It varies 4rm motor 2 motor & supply 2 supply.

What are the difference between CT/PT operated Meter and RRAMR Meter for HT/LT application?

1 Answers  

---

Is there any relevant technique to produce power from light and heat energy of the sun simultaneosly from same rays of light?

0 Answers  

---

How many types of isolator is available for H.T.lines? which one is best for sub-station?

4 Answers  

---

2 v/500amp/hr to 1.80vpc at 20 degree celsious 2v/5ooamp/hr to 1.75 vpc at 77degree farren .this is the capacity of a battery .what is the meaning of this . can i get a detailed explenation

0 Answers  

---

IN TWO WATTMETER METHOD WE GOT W1,W2,WE KNOW V.HOW TO FIND Q????????????

7 Answers   APTransco,

---

hi, i finished b.tech eee in 2008, im worked in dg sets mfg company , now i left job in 6months back, now again i want get job core side, how can i get? is there any couses we have learn to get better oppurtunity? /

0 Answers  

---

Does Lightening arrest requires Earthing?..

5 Answers  

---

why we use taping of transformer on HT side?

4 Answers  

---

how circuit breaker work.. what is the operations taking place inside a circuit breaker when an overcurrent occurs... is it similar to fuse?

0 Answers   LTT,

---

Why squirrel case induction motor bar is skew permanently?

1 Answers   Nesco,

---

why rating of motor in HP

2 Answers   MSL,

---

auto reclosing scheme for radial ehv feeder is to be implemented or not?

1 Answers   State Board,

---