Answer / pandi

in series motor field winding is series to armature winging.
at starting condition we control starating current for
prevent the winding from over current.so flux
low.N=1/flux.so motor rut at dangerous speed.to avoid that
start with load.
in shunt motor field winding is parallel to armature
winding.the field is current is mostly constant.so flux
also constant.sppeed also constant

Answer / ravi prakash

series motors starting torque is very high & hence it should
be started with load only.shunt motor starting torque is
marginal and hence it should be started with least load.

Answer / smaranika

A series motor should be started with load because at no
load the armature current is very less and so is the flux.
Flux is inversely proportional to speed.As a result the
speed increases to a very high valuewhich is dangerous.
A shunt motor should not be started at heavy load because
with heavy load the armature speed decreases as a result
back e.m.f decreases.Decrease in back e.m.f leads to heavy
current flow through the armature.

Answer / ali

in series motor field winding also carries armature current
so that flux is proportinal to armature current.and speed
is inversly proportional to flux i.e is armature current
N=1/Ia hence during starting the current is very low if
there is no load hence speed of the motor is dangerously
high which can cause mechanical damage to the motor.

in shunt motor field winding is parallel to armature
winding.the field is current is mostly constant.so flux
also constant.sppeed also constant

Answer / mayank sharma

if series motor starts without any load,ie open circuited
condition...a very less flux will be generated that is
mainly due to residulal flux and hence speed being inversly
propotional to flux,a speed (theoritiaclly infinite)will be
there at starting and hence its not started at no load in
the begning.
there is no such compulsion in dc shunt motor but running
it on no load in starting ensures that the good amount of
working flux will get generated before load is applied.

Answer / kub&

series motor have few and low resistance windings which
will take time to build up flux. since speed is inversely
proportional to flux,the speed will be very high at
start.

Answer / amirtha

in series motor there will be no residual flux. so there it
have high starting torque,which will lead to to dangerously
high speed.but in shunt motor there is no such condtion

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