Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = f1kw1 / f2kw2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines From no load to full load the slip will slightly increase. slightly decrease. None of these not change. slightly increase. slightly decrease. None of these not change. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The DC generator runs at a speed of 1000 rpm and flux per pole is 0.2 Wb, number of poles are 2 the winding is wave wound and having 480 conductors. The critical speed is 1200 rpm. Then the generated emf ( Eg ) 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. 0 Volt. 2000 Volt. 1500 Volt. 1600 Volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V DC generator is run at full speed without any excitation. The open circuit voltage will be 220 V. about 50 V. zero. about 2 V. 220 V. about 50 V. zero. about 2 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 2, 3, 4 1, 2, 3, 4 and 5 1, 3, 4, 5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt motor has external resistance Ra and Rf in the armature and field circuits respectively. Armature current at starting can be reduced by keeping Ra maximum and Rf minimum Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf maximum Ra maximum and Rf minimum Rf maximum and Ra minimum Ra minimum and Rf minimum Ra maximum and Rf maximum ANSWER DOWNLOAD EXAMIANS APP
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