Electrical Machines A commutator in dc machine provide ----------------- rectification? half wave controlled full wave controlled full wave half wave half wave controlled full wave controlled full wave half wave 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, 3 1, 2, 3 and 4 3 only 1, 2 and 3 1, 3 1, 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For very sensitive and wide speed control, the preferable control method is Field control. Multiple voltage control. Ward-Leonard control. Armature control. Field control. Multiple voltage control. Ward-Leonard control. Armature control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 920 RPM 940 RPM 970 RPM 960 RPM 920 RPM 940 RPM 970 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A Shunt generator running at 1000 rpm has generated emf of 100 V. If the speed increases to 1200 rpm, the generated emf will be nearly 240 V 120 V 140 V 175 V 240 V 120 V 140 V 175 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines 3rd harmonics are eliminated in induction motor by using star connection. V connection. delta connection. zig - zag connection. star connection. V connection. delta connection. zig - zag connection. ANSWER DOWNLOAD EXAMIANS APP
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