Electrical Machines What is the highest possible speed of turbo alternators? 1000 rpm 3000 rpm 4000 rpm 1500 rpm 1000 rpm 3000 rpm 4000 rpm 1500 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable acidity level of power transformer insulating oil is generally taken as 0.5 mg of KOH / gm. 2 mg of KOH / gm. 1 mg of KOH / gm. 0.3 mg of KOH / gm. 0.5 mg of KOH / gm. 2 mg of KOH / gm. 1 mg of KOH / gm. 0.3 mg of KOH / gm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following represents the commutator pitch? Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the front end of the armature. The distance between the staring of first coil and its next successive coil Number of conductors spanned by one coil at the back end of the armature. Number of commutator segments between two successive coils. Number of conductors spanned by one coil at the front end of the armature. The distance between the staring of first coil and its next successive coil Number of conductors spanned by one coil at the back end of the armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net voltage across the armature resistance at the time of plugging will be 6 V 474 V 240 V 234 V 6 V 474 V 240 V 234 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is Fmax. (1/2)Fmax. (3/2)Fmax. 3Fmax. Fmax. (1/2)Fmax. (3/2)Fmax. 3Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4, 5 2, 3, 4 2, 3 ,5 1, 2, 3 2, 3, 4, 5 2, 3, 4 2, 3 ,5 1, 2, 3 ANSWER DOWNLOAD EXAMIANS APP