Electrical Machines In electric locomotives which of the following motor are used ? DC compound motor. DC Shunt motor. DC series motor. Synchronous motor. DC compound motor. DC Shunt motor. DC series motor. Synchronous motor. 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 960 RPM 920 RPM 940 RPM 970 RPM 960 RPM 920 RPM 940 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two generators G1 and G2 are to be operated in parallel to deliver a total current of 60 A. Generator one has a terminal voltage of 280 V on no load and 240 V when supplying 40 A current. Similarly the second generator has a voltage of 300 V when on no load and 240 V when supplying of 50 A of current. The output voltage of each generator will be 238.2 V. 256.4 V. 271.7 V. 240 V. 238.2 V. 256.4 V. 271.7 V. 240 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine current and emf at the terminals are alternating. emf in armature conductors and at the terminals is alternating. current and emf in armature are alternating. current and emf in armature are unidirectional current and emf at the terminals are alternating. emf in armature conductors and at the terminals is alternating. current and emf in armature are alternating. current and emf in armature are unidirectional ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For larger units high torque it is preferred to use Slip induction motor. DC shunt motor. Partial motor. Universal motor. Slip induction motor. DC shunt motor. Partial motor. Universal motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor must started on no load because it would Run at dangerously high speed. Draw more current without producing sufficient torque. Not develop starting torque. Fail to start without load. Run at dangerously high speed. Draw more current without producing sufficient torque. Not develop starting torque. Fail to start without load. ANSWER DOWNLOAD EXAMIANS APP