Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the field winding must be replaced field winding must be excited by low voltage dc supply the armature connection must be reversed the field winding connection must be reversed the field winding must be replaced field winding must be excited by low voltage dc supply the armature connection must be reversed the field winding connection must be reversed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The heat generated in the transformer is dissipated mainly by convection. All of these radiation. conduction. convection. All of these radiation. conduction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 3 only 1, 2 and 3 1, 2, 3 and 4 1, 3 3 only 1, 2 and 3 1, 2, 3 and 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following rotor requires damper winding? Both type rotor. Cylindrical rotor. None of these Salient pole rotor. Both type rotor. Cylindrical rotor. None of these Salient pole rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The flux involved in the emf equation of a transformer has maximum value. rms value. total value. average value. maximum value. rms value. total value. average value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, electric current to the external circuit from armature is given through solid connection. none of above. commutator. slip rings. solid connection. none of above. commutator. slip rings. ANSWER DOWNLOAD EXAMIANS APP
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