Electrical Machines In DC generators, the residual magnetism is of the order of 2.5 %. 15 %. 20 %. 10 %. 2.5 %. 15 %. 20 %. 10 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 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 efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 67.5% 72.5% 82.5% 78.5% 67.5% 72.5% 82.5% 78.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation of the synchronous generator fails, it acts as a/an induction generator. synchronous generator. induction motor. synchronous motor. induction generator. synchronous generator. induction motor. synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be about 100 V. 250 V. zero. very small, say about 2 or 3 V. about 100 V. 250 V. zero. very small, say about 2 or 3 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM in order to eliminate cogging the number of stator slots must be either (B) or (C). an integral multiple of number of rotor slots. unequal to number of rotor slots and skewed in shape. equal to number of rotor slots. either (B) or (C). an integral multiple of number of rotor slots. unequal to number of rotor slots and skewed in shape. equal to number of rotor slots. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The magnetic circuit of a dc shunt generator with negligible armature resistance and brush contact voltage drop remains unsaturated when it delivers full-load current at rated terminal voltage. The brushes are kept in the interpolar axis and speed is maintained constant. When the load is switched off, the terminal voltage would decrease remain the same become zero increase decrease remain the same become zero increase ANSWER DOWNLOAD EXAMIANS APP
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