Electrical Machines What is the necessity of copper brushes in a dc motors? To convert alternating supply current to direct current. To increase the flux cutting by the rotor. To absorb the mechanical shocks produced during running condition. None of these. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. To absorb the mechanical shocks produced during running condition. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The low voltage winding of a 400/230 V single phase 50 Hz transformer is to be connected to keep the magnetization current at the same level in both the cases the voltage at 25 Hz should be 115 V 65 V 460 V 230 V 115 V 65 V 460 V 230 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which machine is used for battery charging? DC series generator. None of these. Compounded DC generator. DC shunt generator. DC series generator. None of these. Compounded DC generator. DC shunt generator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field winding connection of DC shunt motor is changed motor will not run. motor will become slow. It will run in opposite direction. It will run in same direction. motor will not run. motor will become slow. It will run in opposite direction. It will run in same direction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Motor 3 point starter is used to limit the starting current to a safer value. provide protection against Low-Voltage. all of above. provide overload protection. limit the starting current to a safer value. provide protection against Low-Voltage. all of above. provide overload protection. 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 1Ω. 0.23Ω. 0.5Ω. 0.25Ω. 1Ω. 0.23Ω. 0.5Ω. 0.25Ω. ANSWER DOWNLOAD EXAMIANS APP