Electrical Machines During hunting of a synchronous motor damper bar develops torque. negative phase sequence currents are generated. harmonic are developed in the armature circuit. field excitation increases. damper bar develops torque. negative phase sequence currents are generated. harmonic are developed in the armature circuit. field excitation increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In applied voltage is reduced in a dc shunt motor Full load speed. None of these. Full load current. Full load torque. Full load speed. None of these. Full load current. Full load torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature coil is short circuited by brushes when it lies along neutral axis. along field axis. in none of above positions. in any of above positions. along neutral axis. along field axis. in none of above positions. in any of above positions. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is the largest conversion device? Synchronous machine All of these Induction machine DC machine Synchronous machine All of these Induction machine DC machine ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Minimum allowable resistivity of power transformer insulating oil is generally taken as 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 4 X 1012 Ω - cm at 27°C and 0.4 X 1012 1 X 1012 Ω - cm at 27°C and 0.1 X 1012 3 X 1012 Ω - cm at 27°C and 0.3 X 1012 2 X 1012 Ω - cm at 27°C and 0.2 X 1012 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 12. 7. 3. 4. 12. 7. 3. 4. ANSWER DOWNLOAD EXAMIANS APP