Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.649. 0.512. 0.573. 0.443. 0.649. 0.512. 0.573. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by the a 230 V DC motor of armature resistance 0.5 Ω and back emf 200 V is 600 60 660 40 600 60 660 40 ANSWER DOWNLOAD EXAMIANS APP
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. 4. 7. 3. 12. 4. 7. 3. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are 4% and 5% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW? 200 MW and 400MW None of these generator 1 gets over load generator 2 gets over load 200 MW and 400MW None of these generator 1 gets over load generator 2 gets over load ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC shunt generator working on load, the brushes are moved forward in the direction of rotation, as a result of this, commutation will worsen and terminal voltage will rise. improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will fall worsen and terminal voltage will rise. improve and terminal voltage will rise . improve but terminal voltage will fall. worsen and terminal voltage will fall ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer zero voltage regulation is achieved at a load power factor which is zero leading lagging unity zero leading lagging unity ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS