Electrical Machines The rotor power output of 3-phase induction motor is 15 KW. The rotor copper losses at a slip of 4% will be 625 W 700 W 600 W 650 W 625 W 700 W 600 W 650 W 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, 2, 3 and 4 are correct 1, 2 and 3 are correct 1 and 4 are correct 1, 2 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1 and 4 are correct 1, 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 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 efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 72.5% 67.5% 82.5% 78.5% 72.5% 67.5% 82.5% 78.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a DC Shunt Motor having armature resistance of 0.5 Ω and 2A armature current at no-load, when the armature current is changed to 20A at loaded condition the speed is 1000 r.p.m. What is the speed at no-load? 963.8 r.p.m. 4575.4 r.p.m. 1130 r.p.m. 1037.5 r.p.m. 963.8 r.p.m. 4575.4 r.p.m. 1130 r.p.m. 1037.5 r.p.m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum power developed in a cylindrical synchronous machine depends on load angle excitation both 1and 2 synchronous reactance load angle excitation both 1and 2 synchronous reactance ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The power flow of a dc motor, with respect to a DC generator is modified. none of these. reversed. increased. modified. none of these. reversed. increased. ANSWER DOWNLOAD EXAMIANS APP
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