Electrical Machines Which of the following DC generators has rising V-I characteristics? Compound. None of them. Series. Shunt. Compound. None of them. Series. Shunt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field system of an alternator is usually excited 110 / 220 V AC. 230 V AC. 3 - Φ, 50 Hz and 400 V. 250 / 250 V DC. 110 / 220 V AC. 230 V AC. 3 - Φ, 50 Hz and 400 V. 250 / 250 V DC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? It will rotates in normal operation. Either short circuit or open circuit occurs. It will rotates in reverse direction. Fail to start. It will rotates in normal operation. Either short circuit or open circuit occurs. It will rotates in reverse direction. Fail to start. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by s2. sf. sf / 2. f / s. s2. sf. sf / 2. f / s. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A cumulatively compounded dc motor delivers rated load power at rated speed. If the series field is short-circuited, then Ia increases and ωm decreses Ia remains constant but ωm increase both decrese both armature current Ia and speed ωm increase Ia increases and ωm decreses Ia remains constant but ωm increase both decrese both armature current Ia and speed ωm increase ANSWER DOWNLOAD EXAMIANS APP