Electrical Machines Brushes are always placed on--------------- , in order to achieve sparkles commutation? None of these either GNA or MNA GNA MNA None of these either GNA or MNA GNA MNA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC shunt generator having a wave winding supplies 50 lamps, each of 60 W at 120 V. The armature and field resistance are 0.2 Ω and 60 Ω respectively. The current in each armature conductor is 11.5 A. 27 A. 23 A. 13.5 A. 11.5 A. 27 A. 23 A. 13.5 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes 1/4 of the intial value 1/2 of the initial value 4 time the initial value twice the initial value 1/4 of the intial value 1/2 of the initial value 4 time the initial value twice the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is not a necessary condition to be satisfied for synchronising an incoming alternator to an already operating alternator? same voltage magnitude same frequency same phase sequence same prime mover speed same voltage magnitude same frequency same phase sequence same prime mover speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of conductor of a DC motor can be determined by Lenz's law. Fleming's left hand rule. Fleming's right hand rule. Ampere law. Lenz's law. Fleming's left hand rule. Fleming's right hand rule. Ampere law. ANSWER DOWNLOAD EXAMIANS APP
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