GETCO Exam Paper (22-07-2015) A transformer has negative voltage regulation when its load PF is zero leading lagging unity zero leading lagging unity ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Voltage regulation = ((no load voltage)-(full load voltage)/(no load voltage))VR at leading PF = ((I*R*cosφ)-(I*X*sinφ))/VVR at lagging PF = ((I*R*cosφ)+(I*X*sinφ))/V
GETCO Exam Paper (22-07-2015) In case of a balanced three phase sinusoidal AC supply, because of the phase difference rotating magnetic field is produced neutral current is high if load is not balanced all are correct neutral wire is not required, if load is balanced rotating magnetic field is produced neutral current is high if load is not balanced all are correct neutral wire is not required, if load is balanced ANSWER DOWNLOAD EXAMIANS APP
GETCO Exam Paper (22-07-2015) Merz-Price protection is employed for protection of motor alternators circuit breaker transmission lines motor alternators circuit breaker transmission lines ANSWER DOWNLOAD EXAMIANS APP
GETCO Exam Paper (22-07-2015) The magnitude of sum of two sinusoidal AC voltages is equal to the magnitude of each individual voltage, What must be the phase difference between voltages? 60 120 90 180 60 120 90 180 ANSWER DOWNLOAD EXAMIANS APP
GETCO Exam Paper (22-07-2015) In rotating electrical machines, the insulation temperature limit for class B type is 130˚C 180˚C 105˚C 150˚C 130˚C 180˚C 105˚C 150˚C ANSWER EXPLANATION DOWNLOAD EXAMIANS APP insulation Class and temperature limit(in ˚C) is given below:Y - 90A- 105E- 120B-130F-155H-180C- above 180
GETCO Exam Paper (22-07-2015) HVDC transmission is preferred to EHV AC because System stability can be improved Its terminal equipment are inexpensive VAR compensation is not required in it Harmonic problem is avoided System stability can be improved Its terminal equipment are inexpensive VAR compensation is not required in it Harmonic problem is avoided ANSWER DOWNLOAD EXAMIANS APP
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