Electrical Machines What is the reason for stationary armature essential in alternators above 5 KVA? Insulation requirement is less. Collecting of large current is simple. Operating cost is less. All of these Insulation requirement is less. Collecting of large current is simple. Operating cost is less. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will worsen and terminal voltage will rise. improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will fall worsen and terminal voltage will rise. improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will fall ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5Ω and back back emf 200 V is 400 A. 440 A. 40 A. 44 A. 400 A. 440 A. 40 A. 44 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, 1. physically, the brush axis is along the direct axis 2. physically, the brush axis is along the interpolar axis 3. schematically, the brush axis is along the direct axis 4. schematically, the brush axis is along the quadrature axis 5. armaturemmf is directed along the brush axis From these, the correct statements are 1 , 3, 5 2, 3, 5 1, 4,5 2, 4, 5 1 , 3, 5 2, 3, 5 1, 4,5 2, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 8 Ω. 2 Ω. 10 Ω. 4 Ω. 8 Ω. 2 Ω. 10 Ω. 4 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the load current and flux of a DC motor are held constant and voltage applied across it armature is increased by 5%, the speed of the motor will Depends on other factor. Reduce by 5%. Increase by 5%. Remain unchanged. Depends on other factor. Reduce by 5%. Increase by 5%. Remain unchanged. ANSWER DOWNLOAD EXAMIANS APP