MGVCL Exam Paper (30-07-2021 Shift 1)
___ is the short time reduction in the rms voltage between 0.1 to 0.9 p.u for a duration of ___

Voltage sag, 0.5 cycle to 1 minute.
Voltage swell, greater than 1 minute
Voltage sag, greater than 1 minute
Voltage swell, 0.5 cycle to 1 minute.

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MGVCL Exam Paper (30-07-2021 Shift 1)
For protection of inter-turn fault in transformer, the relays preferred are

Overcurrent relay and differential relay
Buchholz's relay, overcurrent relay and differential relay
Overcurrent relay and Buchholz's relay
Buchholz's relay and differential relay

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MGVCL Exam Paper (30-07-2021 Shift 1)
In a 3-phase, 4-wire, 400/230 V system, a lamp (L1) of 100 W is connected to one phase and neutral and a lamp (L2) of 150 W is connected to the second pahse and neutral. If the neutral wire is disconnected accidently, what will be the voltage across a 100 W lamp (L1)?

180V
120V
240V
160 V

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MGVCL Exam Paper (30-07-2021 Shift 1)
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 aiding.

932 mH
1270 mH
1135 mH
730 mH

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