Answer / vivek kumar

at no load the current passing through the field is minimum
and almost zero ,so the flux at the field will be also
almost zero and we know that the speed is inversly
perpotional to the flux in the field so due to almost zero
flux the speed will be maximum and almost infinite at the
starting and it will cause damege of the beerings armatures
shaft due to sudden break in its inertia.

Answer / m_anwar

The speed of a series motor with no load connected to it
increases to the point where the motor may become damaged.
Usually, either the bearings are damaged or the windings
fly out of the slots in the armature. There is a danger to
both equipment and personnel. Some load must ALWAYS be
connected to a series motor before you turn it on. This
precaution is primarily for large motors. Small motors,
such as those used in electric hand drills, have enough
internal friction to load themselves.

Answer / saidireddy

series motors are not operated without load because its having high starting current due to this at starting time necessary to add the load otherwise it will rotates dangerous speed............

Answer / sivasamy83

The seriesw motor is not started without load because the
starting Torque high.......

Answer / lokesh kumar

Series motor cannot be started without load because of high
starting torque. Series motor are used in Trains, Crane
etc...

Answer / dharanidharan

There is no parallel path for current, since the connection
is series.

so that starting current is high

which produce high starting torque

motor runs in HIGH SPEED, so it is started with load

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