Electrical Machines The 3 - Φ induction motor with rotor circuit open will run normally. make noise. get over heated. not run. run normally. make noise. get over heated. not run. 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%. 970 RPM 920 RPM 940 RPM 960 RPM 970 RPM 920 RPM 940 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 15.1 Ω 31.9 Ω 15.9 Ω 31.1 Ω 15.1 Ω 31.9 Ω 15.9 Ω 31.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. kept constant to certain value. decreased. increased. remains same. kept constant to certain value. decreased. increased. remains same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are not a self starting motor? both 1 and 2 None of these 1-phase induction motor 3-phase induction motor both 1 and 2 None of these 1-phase induction motor 3-phase induction motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 1Ω. 0.5Ω. 0.25Ω. 0.23Ω. 1Ω. 0.5Ω. 0.25Ω. 0.23Ω. ANSWER DOWNLOAD EXAMIANS APP