DC Motors The main disadvantage of the Ward-Leonard control method is High maintenance cost High initial cost All of these Low efficiency at high loads High maintenance cost High initial cost All of these Low efficiency at high loads ANSWER DOWNLOAD EXAMIANS APP
DC Motors Armature reaction in dc motor is increased When the armature current increases By interpoles When the field current increases When the armature current decreases When the armature current increases By interpoles When the field current increases When the armature current decreases ANSWER DOWNLOAD EXAMIANS APP
DC Motors Differentially compound D.C. motors can find applications requiring Low starting torque Variable speed High starting torque Frequent on-off cycles Low starting torque Variable speed High starting torque Frequent on-off cycles ANSWER DOWNLOAD EXAMIANS APP
DC Motors Three point starter can be used for Compound motor only Shunt motor only Both shunt and compound motor Series motor only Compound motor only Shunt motor only Both shunt and compound motor Series motor only ANSWER DOWNLOAD EXAMIANS APP
DC Motors The torque developed by a dc motor is directly proportional to Armature resistance × applied voltage None of the listed here Armature resistance × armature current Flux per pole × armature current Armature resistance × applied voltage None of the listed here Armature resistance × armature current Flux per pole × armature current ANSWER DOWNLOAD EXAMIANS APP
DC Motors As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit Armature is temporarily open circuited A resistance is connected parallel to the armature A resistance is connected in series with armature A high value resistor is connected across the field winding Armature is temporarily open circuited A resistance is connected parallel to the armature A resistance is connected in series with armature A high value resistor is connected across the field winding ANSWER DOWNLOAD EXAMIANS APP
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