Electrical Machines A 3-phase 6 pole 50 Hz induction motor is running at 5% slip.What is the speed of the motor? 900 rpm 950 rpm 1000 rpm 850 rpm 900 rpm 950 rpm 1000 rpm 850 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A slip ring Induction motor runs at 290 rpm at full load, when connected to 50 Hz supply. Determine the number of poles and slip. P = 40, s = 5.79 %. P = 60, s = 0.96 %. P = 20, s = 3.33 %. P = 50, s = 4.43 %. P = 40, s = 5.79 %. P = 60, s = 0.96 %. P = 20, s = 3.33 %. P = 50, s = 4.43 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 2, 3 and 4 1, 2, and 3 1 and 3 1, 2 and 4 2, 3 and 4 1, 2, and 3 1 and 3 1, 2 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC compound motor has tertiary winding. both shunt and series field winding. only shunt field winding. only series field winding. tertiary winding. both shunt and series field winding. only shunt field winding. only series field winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In escalator which motor is used? Universal motor. 3 - φ IM. 1 - φ IM. DC shunt motor. Universal motor. 3 - φ IM. 1 - φ IM. DC shunt motor. ANSWER DOWNLOAD EXAMIANS APP