Answer / kavitha

If the supply is given ,the voltage increase form low to
high level .the current also increases so to reduce the
high starting currents & protect the motor we use starter.

Answer / priya

Starters are used to limit high currents during starting by adding resistors in series with armature circuit which are excluded gradually when the motor speed increases. High starting currents are due to
1. In case of DC motor, initially back emf(E) is zero therefore I=(V-E)/Ra becomes V/Ra. Generally Ra armature circuit resistance is very low hence I is very high during starting. When speed increases back emf increases and I reduces therefore resistors can be excluded.
2. In synchronous motors starters are not used

Answer / saranya natarajan

To limit the starting current
Initially all resistances will be included to limit the
starting current. Slowly the resistances will be excluded
one by one and gradually the current increases and motor
runs in rated speed.

Answer / ravi raj

starter gives normal rating current & voltage to start the
motors, to gives over load the starter is triped.

Answer / mohammad rashid

The motor stsrter will trip an overload relay the current
to the motor is excessive, It will also remove power from
all conductors to the motor.

Answer / pradyumna chandra panda

to provide OVER LOAD RELEASE COIL(Relay) to save the moto winding from more current than rated.

hot water tank,top element 240v across,the bottom 120v across,why?

1 Answers  

what is the reactance,capacitance & impedence electrical armoured & unarmored Cables.

0 Answers  

Why we use RYB phase sequence?

3 Answers  

State how to produce a constant rotating field by application of alternating currents to stator armature of a three-phase squirrel-cage induction motor

0 Answers   Jindal,

why test lamp didn't glow across 500v megger?

4 Answers   Aurobindo,

what meaning of gd squre

1 Answers  

what is AH of battery

6 Answers   NSIC,

what is zero sequence curr ent ?

4 Answers  

Why only 1ph,2ph,3ph supplies are universally used?? Why not 4ph or 5ph??

4 Answers  

What does the letter CTNM in negative phase sequence relay means?

0 Answers  

What is Generator Protection & Transformer Protection?

3 Answers   Areva,

why dc series motor has high starting torque

2 Answers