Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at leading power factor. unity power factor. any of the above. lagging power factor. leading power factor. unity power factor. any of the above. lagging power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced the field winding connection must be reversed the armature connection must be reversed field winding must be excited by low voltage dc supply the field winding must be replaced the field winding connection must be reversed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If input of a transformer is square wave the output will be pulsed wave. sine wave. square wave. triangular wave. pulsed wave. sine wave. square wave. triangular wave. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The effect of ------------------ on main field flux is armature reaction? armature mmf armature flux armature current All of these armature mmf armature flux armature current All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Commutators in DC machines have a role of which converts AC to DC. high voltage DC to low voltage DC. none of these. Both AC to DC and DC to AC. AC to DC. high voltage DC to low voltage DC. none of these. Both AC to DC and DC to AC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines which of the following type of brush and their application is/are correct copper graphite → low voltage high current density electro graphite → large ratings All of these carbon brush → normal ratings copper graphite → low voltage high current density electro graphite → large ratings All of these carbon brush → normal ratings ANSWER DOWNLOAD EXAMIANS APP