Electrical Machines A DC Shunt Motor having shunt field resistance of 250 Ω and armature resistance of 0.5 Ω is connected to 250 V supply and load current of 21 A. What is the back emf generated ? 230 V. 240 V. 150 V. 210 V 230 V. 240 V. 150 V. 210 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the phase difference between two windings of A.C servomotor ? 60°. 120°. 30°. 90°. 60°. 120°. 30°. 90°. 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 more than 6 V less than 6 V zero 6 V more than 6 V less than 6 V zero 6 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Motors for fans and pumps are selected in the rpm range 720 to 920. 1440 to 2880. 375 to 500. 500 to 720. 720 to 920. 1440 to 2880. 375 to 500. 500 to 720. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The ___________________ generator has the poorest voltage regulation. under-compounded. over compounded. shunt. differential compounded. under-compounded. over compounded. shunt. differential compounded. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC cumulatively compounded motor delivers rated load torque at rated speed. If the series field is short-circuited, then the armature current and speed will increase and decrease respectively both decrease decrease and increase respectively both increase increase and decrease respectively both decrease decrease and increase respectively both increase ANSWER DOWNLOAD EXAMIANS APP