Electrical Machines In a 6 pole DC machine, 90 mechanical degrees correspond to which of the following electrical degree? 270. 45. 30. 180. 270. 45. 30. 180. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following windings are necessary in case of all dc machines? closed winding wave winding lap winding open type winding closed winding wave winding lap winding open type winding ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC compound motor has tertiary winding. only shunt field winding. both shunt and series field winding. only series field winding. tertiary winding. only shunt field winding. both shunt and series field winding. only series field winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 3, 4, 5 1, 2, 5 2, 4, 5, 6 2, 3, 6 3, 4, 5 1, 2, 5 2, 4, 5, 6 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the cause of rapid brush wear may be rough commutator surface. severe sparking. any of above. imperfect contact. rough commutator surface. severe sparking. any of above. imperfect contact. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For successful parallel operation of two single phase transformers, the most essential condition is that their turn- ratios are exactly equal KVA ratings are equal polarities are properly connected percentage impedances are equal turn- ratios are exactly equal KVA ratings are equal polarities are properly connected percentage impedances are equal ANSWER DOWNLOAD EXAMIANS APP
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