Electrical Machines which of the following type of brush and their application is/are correct carbon brush → normal ratings electro graphite → large ratings copper graphite → low voltage high current density All of these carbon brush → normal ratings electro graphite → large ratings copper graphite → low voltage high current density All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the field winding connection must be reversed the field winding must be replaced the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding connection must be reversed the field winding must be replaced the armature connection must be reversed field winding must be excited by low voltage dc supply ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? To increase the flux cutting by the rotor. To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. None of these. To increase the flux cutting by the rotor. To convert alternating supply current to direct current. To absorb the mechanical shocks produced during running condition. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause double frequency currents in the rotor. All of these vibrations. heating of rotor. double frequency currents in the rotor. All of these vibrations. heating of rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines On switching a DC motor to DC supply mains, it is found to rotate in the direction opposite to that for which it is designed. The DC motor is have an equal number of electrons and protons. Series shunt. Differentical compound. Cummulative compound. have an equal number of electrons and protons. Series shunt. Differentical compound. Cummulative compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generator, brushes are always placed along magnetic neutral axis. load axis. armature axis. geometrical neutral axis. magnetic neutral axis. load axis. armature axis. geometrical neutral axis. ANSWER DOWNLOAD EXAMIANS APP
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