Electrical Machines In which of the following speed control of DC motor the speed obtained is below than the rated speed? Armature circuit resistance control. Armature voltage control. Any of above. Field resistance control. Armature circuit resistance control. Armature voltage control. Any of above. Field resistance control. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the handle of a three point starter goes to back to OFF position, it may be due to zero or very low voltage supply. high filed circuit resistance. all of these. over load. zero or very low voltage supply. high filed circuit resistance. all of these. over load. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A Shunt generator running at 1000 rpm has generated emf of 100 V. If the speed increases to 1200 rpm, the generated emf will be nearly 240 V 140 V 175 V 120 V 240 V 140 V 175 V 120 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory performance of 3-phase 480V, 60 Hz induction motor, the supply voltage at 50 Hz should be equal to 350 V. 420 V. 400 V. 480 V. 350 V. 420 V. 400 V. 480 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward-Leonard system for controlling the speed of a DC motor is used where Very fine speed control over the whole range from zero to normal speed is required. The speed in both the direction is required. All of above. The accuracy in speed control is required. Very fine speed control over the whole range from zero to normal speed is required. The speed in both the direction is required. All of above. The accuracy in speed control is required. 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 2, 3, 4, 5 1, 2, 3 2, 3 ,5 2, 3, 4 2, 3, 4, 5 1, 2, 3 2, 3 ,5 ANSWER DOWNLOAD EXAMIANS APP