Answer / vinodh.t,sathavahana ispat ltd

1.constant power :in single phase power varies sinosoidally
from zero to a peak value at twice the supply
frequency.this pulsating nature of power is objectionable
for many application in 3 phase the poiwer supplied at all
instants of time is constant
2.the output of a 3phase machine is greater than that of a
single phase machine for a given volume and weight of
machine.
3.the 3 phase motor are much smaller and cheap than single
phase

Answer / mahantesh

Three phase carry large current than a single phase current,for larger loads the cross section of conductor is larger in single phase than three phase and single phase cannot be transmitted to larger distance than the three phase,line losses are small as compared to single phase so we prefer three phase instead of single phase

Answer / manish singla

i agree with Reply by Mr. Vinodh.t,sathavahana Ispat Ltd.

Warm Regards,

Answer / prasad.v

because in one phase if there is any shortage or short
circuit may happen apart from this if we use one phase
current there may be more possible to low voltage we can see
that some house light will be more dim so if we three phase
if any of the has low voltage we can change the phase so we
are preferring 3 phase than 1 phase

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