Electrical Machines Which of the following is the largest conversion device? DC machine All of these Induction machine Synchronous machine DC machine All of these Induction machine Synchronous machine ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 400 / 200 V, Y - Y connected wound rotor induction motor has 0.06 Ω rotor resistance and 0.3 Ω standstill reactance per phase. To make the starting torque equal to maximum torque of the motor the additional resistance required 0.78 Ω. 0.45 Ω. 0.24 Ω. 0.66 Ω. 0.78 Ω. 0.45 Ω. 0.24 Ω. 0.66 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 500 V, 55 kVA single phase alternator has an effective resistance of 0.5 Ω. An excitation current of 10 A produces 200 A armature current on short circuit and an emf of 450 V on per circuit. The synchronous reactance will be 2.241 Ω. 2.74 Ω. 2.781 Ω. 25.564 Ω. 2.241 Ω. 2.74 Ω. 2.781 Ω. 25.564 Ω. 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 3 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1 and 4 are correct 1, 2 and 3 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The starting resistance of DC motor is generally Low. Infinitely large. 1000 ohms. around 500 ohms. Low. Infinitely large. 1000 ohms. around 500 ohms. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Skewing of the rotor in a 3 - Φ squirrel cage induction motor reduces noise and parasitic torque, but increase starting and pull-out torque. noise, parasitic torque, starting torque and pull out torque. noise, parasitic and starting torque, but increase pull out torque. noise and pullout torque, but increase parasitic and starting torque. noise and parasitic torque, but increase starting and pull-out torque. noise, parasitic torque, starting torque and pull out torque. noise, parasitic and starting torque, but increase pull out torque. noise and pullout torque, but increase parasitic and starting torque. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS