Electrical Machines An inverted V curve of synchronous motor shows variation of power factor and DC excitation at constant load. power factor and supply voltage during hunting. supply voltage and excitation current at constant load. supply voltage and field current at constant excitation. power factor and DC excitation at constant load. power factor and supply voltage during hunting. supply voltage and excitation current at constant load. supply voltage and field current at constant excitation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A separately-excited DC generator, running at rated speed, has 6 volts across its armature terminals with no field current. When field winding is excited with one ampere, the voltage builds up to 250 V at no load. In case field current is reduced to zero, with the speed remaining unaltered, the armature terminal voltage would be 6 V more than 6 V less than 6 V zero 6 V more than 6 V less than 6 V zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 38% 60% 40% 68% 38% 60% 40% 68% 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 carbon brush → normal ratings All of these copper graphite → low voltage high current density electro graphite → large ratings carbon brush → normal ratings All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum power developed in cylindrical synchronous machine is occurs at a load angle of 90o. Greater than 90o. less than 90o. 0o. 90o. Greater than 90o. less than 90o. 0o. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the eddy current loss if the supply frequency of a transformer becomes double? Doubled. Eight times. Four times. Remains same. Doubled. Eight times. Four times. Remains same. ANSWER DOWNLOAD EXAMIANS APP
EXAMIANS