Electrical Machines The fall in speed of the DC generator due to increase in load can be corrected by cooling the armature. increasing the excitation. reducing the load voltage. increasing the input to the prime mover. cooling the armature. increasing the excitation. reducing the load voltage. increasing the input to the prime mover. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the e.m.f. generated by a 4 pole lap connected DC Generator rotating at 1500 r.p.m.? Its flux per pole is 0.4 mWb and total no of armature conductors is 1000. 40 volts. 30 volts. 10 volts. 20 volts. 40 volts. 30 volts. 10 volts. 20 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.75 p.u 0.5 p.u 0.125 p.u 0.25 p.u 0.75 p.u 0.5 p.u 0.125 p.u 0.25 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 0.5Ω. 1Ω. 0.23Ω. 0.25Ω. 0.5Ω. 1Ω. 0.23Ω. 0.25Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Maximum allowable tan - delta (tanδ) of dielectric dispassion factor of power transformer insulating oil is generally taken as 3 at 90°C. 0.5 at 90°C. 1 at 90°C. 2 at 90°C. 3 at 90°C. 0.5 at 90°C. 1 at 90°C. 2 at 90°C. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, electric current to the external circuit from armature is given through none of above. commutator. solid connection. slip rings. none of above. commutator. solid connection. slip rings. ANSWER DOWNLOAD EXAMIANS APP