Electrical Machines The slight curvature at the lower end of the OCC of a self excited DC generator is due to high speed. magnetic inertia. residual flux. high field resistance. high speed. magnetic inertia. residual flux. high field resistance. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a 3 - Φ induction motor is clockwise when it is supplied with 3 - Φ sinusoidal voltage having phase sequence A - B - C. For counterclockwise rotation of motor, the phase sequence of the supply should be B - C - A or C - A - B. B - C - A. A - C - B. C - A - B. B - C - A or C - A - B. B - C - A. A - C - B. C - A - B. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a short circuit test on a transformer is performed at 25 V, 50 Hz, the drawn current is I1. If the test is performed by 25 V and 25 Hz and power drawn current is I2, then I1 = I2 I1 < I2 None of these I1 > I2 I1 = I2 I1 < I2 None of these I1 > I2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to reduce hysteresis loss only. reduce both eddy current and hysteresis loss. increase the permeability. reduce eddy current loss only. reduce hysteresis loss only. reduce both eddy current and hysteresis loss. increase the permeability. reduce eddy current loss only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of these types of motor is self starting? None of these. Poly-phase induction motor. Single phase induction motor. Poly-phase synchronous machine. None of these. Poly-phase induction motor. Single phase induction motor. Poly-phase synchronous machine. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine, for the same value of Æ, Z and N; which one of the following statements is correct? Armature emf depends on weather the machine is running as a motor or generator. Armature emf is more with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is less with wave winding than with lap winding. Armature emf depends on weather the machine is running as a motor or generator. Armature emf is more with wave winding than with lap winding. Armature emf is same as long as the flux density in the air gap remains the same. Armature emf is less with wave winding than with lap winding. ANSWER DOWNLOAD EXAMIANS APP