Electrical Machines An induction motor has synchronous speed of 1500 rpm. What will be the slip when it is running at a speed of 1450 rpm? +3% -3.33% +3.33% -3% +3% -3.33% +3.33% -3% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage across the open circuited field termninals of a synchorous machine under slip test is DC. AC of supply frequency. A modulated supply frequency AC voltage with slip frequency envelop. DC of slip frequency. DC. AC of supply frequency. A modulated supply frequency AC voltage with slip frequency envelop. DC of slip frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The results of a slip test for determining direct axis (Xd) and quadrature axis (Xq) reactances of a star connected salient pole alternator are given below Phase values: Vmax = 108 V ; Vmin = 96 V Imax = 12 A ; Imin = 10 A Hence the two reactances will be Xd = 10.8Ω and Xq = 8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω Xd = 8Ω and Xq = 10.8Ω Xd = 10.8Ω and Xq = 8Ω Xd = 9.6Ω and Xq = 9Ω Xd = 9Ω and Xq = 9.6Ω Xd = 8Ω and Xq = 10.8Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 960 RPM 940 RPM 970 RPM 920 RPM 960 RPM 940 RPM 970 RPM 920 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The magnetic circuit of a dc shunt generator with negligible armature resistance and brush contact voltage drop remains unsaturated when it delivers full-load current at rated terminal voltage. The brushes are kept in the interpolar axis and speed is maintained constant. When the load is switched off, the terminal voltage would remain the same increase become zero decrease remain the same increase become zero decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Field winding of a DC series motor is usually provided with thick wire as it carries large load current. in order to reduce eddy current to provide large flux. to provide large flux. to reduce the insulation of materials. as it carries large load current. in order to reduce eddy current to provide large flux. to provide large flux. to reduce the insulation of materials. ANSWER DOWNLOAD EXAMIANS APP
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