Answer / qureshi majid

Shunt motors are started directly through line,which may be
damaging to the armature and they need special starter
avoiding said damage,where as series motors have high
starting torque with load.without load, starting must be
avoided because empty running can get very high speed
exceeding limit may cause serious damage to the system .

Answer / md.asaduzzaman

as in series motor torque proportional to flux.current
&flux=current
so,t=i^2so,in ac &dc alws,t=+ve.
and also high starting torque,
but in shunt t=i
as,flux cnst,flux depends on sply voltagein ac it =-ve
so.alws series motor is used.

Answer / k.prakashchandra

Series motor is called universal motor as it works on both
AC and DC

Answer / natha

A series-wound motor is referred to as a universal motor when it has been designed to operate on either AC or DC power. The ability to operate on AC is because the current in both the field and the armature (and hence the resultant magnetic fields) will alternate (reverse polarity) in synchronism, and hence the resulting mechanical force will occur in a constant direction.Induction motors can't turn a shaft faster than allowed by the power line frequency. By contrast, universal motors generally run at high speeds.
torque proportional to current^2

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