MGVCL Exam Paper (30-07-2021 Shift 2)
Which one of these is not a monitoring and diagnostic test for transformer oil?

Volatility Level Analysis
Dissolved Metals Analysis
Furanic Compound Analysis
Dissolved Gas Analysis

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
A 50 Hz synchronous generator is connected to an infinite bus through a line. The p.u. reactances of generator and the line are j0.3 p.u. and j0.2 p.u. respectively. The generator no load voltage is 1.1 p.u. and that of infinite bus is 1.0 p.u. The inertia constant of the generator is 4 MW-sec/MVA. Determine the frequency of natural oscillations if the generator is loaded to 60% of its maximum power transfer capacity and small perturbation in power is given.

1.62 Hz
1.32 Hz
1.52 Hz
1.42 Hz

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
The voltage applied to a transformer primary is increased keeping V/f constant. With this, the core loss ____ and the magnetizing current (Im) ____

decreases, increases
remains constant, decreases
increases, increases
increases, remains constant

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP

MGVCL Exam Paper (30-07-2021 Shift 2)
A coil having an inductance of 100 mH is magnetically coupled to another coil having an inductance of 900 mH. The coefficient of coupling between the coils is 0.45. Calculate the equivalent inductance if the two coils are connected in series opposing.

1270 mH
1135 mH
730 mH
932 mH

ANSWER EXPLANATION DOWNLOAD EXAMIANS APP