Answer / manoj tyagi

1.for obtaining variable o/p voltage
2.for interconnecting power s/s having voltage ratios,npy
differing far from unity
3.for starting induction $synchronous motor

Answer / sudhir singh

For obtaining variable output voltage we need auto
transformer because in auto transformer much cupper is
saved.
The autotransformer is used as voltage regulator,in
excitation of various machine.

Answer / meenakshi

it has superior voltage regulation,higher efficiency, n
copper saving. and its mainly used to giv boost to
distribution cable for correcting voltage drop,as furnace
transformer for gettn a convenient supply to suit the
furnace winding,as interconnectng transformer n also as
control equipment.

Answer / m c gupta

To get the step down voltage economically as compared to
two winding transformer

Answer / raul

auto- transfomer is used bcoz of its efficiency n ability
to conduct by tranfomation n elecrically and wide range of
voltage variations available ............it is used in
starting 3-phase induction motor..........variac in
laboratory, for voltage control in power system etc

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1 Answers  

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2 Answers