Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.573. 0.649. 0.512. 0.443. 0.573. 0.649. 0.512. 0.443. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if the field flux axis is ahead of the armature field axis in the direction of rotation, the machine operating is asynchronous motor. asynchronous generator. synchronous generator. synchronous motor. asynchronous motor. asynchronous generator. synchronous generator. synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the developed torque DC Series Motor having armature resistance of 0.2 Ω and taking armature current of 60 A is connected to 250 V supply. Considered brush drop of 1 V each. 266.20 N-m. 133.22 N-m cant be determined. 234.76 N-m. 266.20 N-m. 133.22 N-m cant be determined. 234.76 N-m. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Demagnetization effects which of the following? both B and C commutation reduces the terminal voltage reduction in main field flux both B and C commutation reduces the terminal voltage reduction in main field flux ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the inequality of air-gap flux on the top and bottom halves of the armature is removed the interpoles produce additional flux to augment the developed torque the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the inequality of air-gap flux on the top and bottom halves of the armature is removed the interpoles produce additional flux to augment the developed torque ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a stepper motor the detente torque means maximum of the static torque with the phase winding unexcited. maximum of the static torque with the phase winding excited. minimum of the static torque with the phase winding excited. minimum of the static torque with the phase winding unexcited. maximum of the static torque with the phase winding unexcited. maximum of the static torque with the phase winding excited. minimum of the static torque with the phase winding excited. minimum of the static torque with the phase winding unexcited. ANSWER DOWNLOAD EXAMIANS APP