Electrical Machines If in a sub – station there is one 132 / 33 kV transformer whose secondary is connected with primary of one 33 / 11 kV transformer, the total transformation ratio of the sub – station will be, 12. 7. 3. 4. 12. 7. 3. 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines On which of the following factor/factors the speed of a DC motor depends upon? Field flux. All of these. Applied voltage. Armature current. Field flux. All of these. Applied voltage. Armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements: To control the speed of a dc shunt motor above the base speed over a reasonably wide range, the motor must 1. have compensating winding 2. have interpole winding 3. be started using a 3-point starter 4. be started using a 4-point starter Of these statements 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 3 are correct 2 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 3 are correct 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + Ia. E = V + IaRa. E = V – IaRa. E = V + Ra. E = V + Ia. E = V + IaRa. E = V – IaRa. E = V + Ra. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starter is not used with large DC motor for starting, it will provide execessive voltage drop in line. damage the armature and commutator. draw a starting current many times its rated full load current. all of above. provide execessive voltage drop in line. damage the armature and commutator. draw a starting current many times its rated full load current. all of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the effect of armature reaction ? Both option B and C. Armature flux distorts the main field flux. None of the options. Armature flux weakens the main field flux. Both option B and C. Armature flux distorts the main field flux. None of the options. Armature flux weakens the main field flux. ANSWER DOWNLOAD EXAMIANS APP
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