Electrical Machines The residual magnetism of a self-excited dc generator is lost. To build up its emf again 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 the field winding connection must be reversed the field winding must be replaced the armature connection must be reversed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When operating, two or more transformers in parallel, % impedance of these transformers should be such that actual impedance of all transformers would be same. proportionate to MVA rating of transformers. inversely proportional to MVA rating of transformers. same. such that actual impedance of all transformers would be same. proportionate to MVA rating of transformers. inversely proportional to MVA rating of transformers. same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines shape of net flux density is? flat tapped or trapezoidal sine wave peaky in nature saddle shape flat tapped or trapezoidal sine wave peaky in nature saddle shape ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation of the synchronous generator fails, it acts as a/an synchronous generator. synchronous motor. induction generator. induction motor. synchronous generator. synchronous motor. induction generator. induction motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series generator is connected in series to a feeder having 0.5Ω resistance to boost the voltage. The induced voltage is given by Eg = 0.6Ia, Ra = 0.2Ω and Rs = 0.3Ω. Find the voltage boosted by the generator, when delivering 400 Amp? 90 V. 40 V. 60 V. 30 V. 90 V. 40 V. 60 V. 30 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An inverted V-curve of synchronous motor shows the variation of supply voltage and field current at constant excitation power factor and dc excitation at constant load All of these power factor and supply voltage during hunting supply voltage and field current at constant excitation power factor and dc excitation at constant load All of these power factor and supply voltage during hunting ANSWER DOWNLOAD EXAMIANS APP