Electrical Machines Sparkless commutation can be achieved by employing any one or more of the above methods. compensating winding. inter poles. high resistance carbon brushes. any one or more of the above methods. compensating winding. inter poles. high resistance carbon brushes. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be halved. It will remain the same. It will be doubled. It will becomes four times. It will be halved. It will remain the same. It will be doubled. It will becomes four times. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by increasing field excitation. compensating winding and commutating poles. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. increasing field excitation. compensating winding and commutating poles. shifting the brush axis from GNA to MNA. fixing the brush axis inline with the pole axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction of an unsaturated DC machine is crossmagnetising. magnetising. none of above. demagnetising. crossmagnetising. magnetising. none of above. demagnetising. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Iron losses in a DC machine are independent of variation in speed. load. speed and voltage. voltage. speed. load. speed and voltage. voltage. ANSWER DOWNLOAD EXAMIANS APP