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, producing a much greater increase in the torque. With no load connection to the motor, the value of I a is very small. So, the speed of the motor will be extremely large. For this reason that series motors are never used unless they are directly connected to the load. This is the principle characteristics of a series motor. What are its uses? Uses: It is used in trains and cranes. Back e.m.f.: If a conductor is rotated inside a magnetic field a voltage will be induced in. This induced voltage is opposite to the applied voltage and therefore, it called back e.m.f. What causes the extraordinarily fast voltage drop with increasing load on a di...
Help to people supply all information Machine and machine parts such as turbine, boiler , car, engine and so on