“ Series motors are never used unless they are directly connected to load”- why?

In a series motor the flux depends upon the current in the series field, which is the same current that flows through the armature. At light loads the armature current is small; therefore the flux and torque are small. An increase in the load increases both the armature current and the flux.

The basic speed equation

S = Vt - IaRa - IaRa

KФ

Since the current in the series field is the armature current, the equation may be rewritten substituting Ia for Ф.

S = Vt - IaRa - IaRa

KIa

With no load connection to the motor the value of I is very small. The numerator of the speed equation is large, while the denominator is very small, indicating that the speed of the motor will be extremely large. In fact, the speed of the motor may reach such a value as to cause the centrifugal force to destroy the motor. It is this reason that series motors are never used unless they are directly connected to the load.

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How to Calculate Heat Rate of Generator Engine?

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Packing, Seals and Gaskets

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Why a dc generator fails to build up voltage?

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what is the difference between long shunt and short shunt dc generator?

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Therbligs and Basic 17 motion name of therblig

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Various Methods of Drawing Flow Nets

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Which type of Battery connection Series or Parallel Connection is used for Diesel Generator?

Diesel Generator Battery Connection Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To remove the possibility of arching, remove the negative battery cable is first and attach the negative battery last. When using jumper cables to start the engine make sure to connect the cables in parallel Positive to positive and negative to negative. When using external electrical source to start the engine, turn the disconnect switch to the OFF position. Remove the key before attaching the jumper cables. To avoid damage to engine parts do not connect jumper starting or battery charging cable to any fuel system or electronic component. Battery Parallel Connection: The accompanying illustration shows a typical parallel battery connection. This arrangement doubles the cranking amperage. Battery Series Connection: This illustration shows a typical

what is PIV drive? Why is PIV drive more effective than any other system of drive?

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What are the main components of Automobile?

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“Equalizer connection is needed in lap winding armature but not in wave winding “ why ?

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