Answer / gajanan

in rotor resistance starter external resistance made
connect across rotor winding to reduce rotor current which
consequently reduce starting current.

in case of sq. cage motor there are rotor conductors short
circuited permenantly at end rings and ext resistance can't
connect across it.

Answer / sennapparajan

slip ring motors normally used where ever high stsrting
torque required. by connencting external resistence through
slip rings we can increase the starting torque. so that the
motor designed with slip rings.

at normal case sqrl cage motor will be used. its rotor
conducter shorted permanently./ and to reduce this motor
starting current sar-delta sarters can be used.

Answer / umang

in case of SQ motors, the rotors are shorted and in case of
slip ring motors the exterrnal resistance added with rotor
ckt. to get high starting torque along with limiting
starting current.So when the rotor achieves its full speed
hthe resistaces are shorted by slip rings.which help to get
high stating torque.

Answer / felixraj

In SQ IM rotor bars are shorted permanently by the end
rings,there was no possibility to vary the resistance.
In slip ring it was a wond rotor so the end terminals are
brought out and R can be easily varied by the help of slip rings

Answer / gopi

in squrielcage induction motor the rotor bars are short
circuited. there is no provision of including resistances
on rotor side.
but in slip induction motor, the rotor bars are connected
to slip rings for providing and an external resistances.
thats why tha rotor resistance starter can be used in
only slip ring induction motor.

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