MGVCL Exam Paper (30-07-2021 Shift 1)
Murray loop test is performed on a faulty cable 300 m long. At balance, the resistance connected to the faulty core was set at 15 Ω and the resistance of the resistor connected to the sound core was 45 Ω. Calculate the distance of the fault point from the test end.
Intern turn winding fault can be easily detect by differential protection relay. Also detect by buchholz relay (gas operated relay), cause buchholz relay is used to detect the internal fault of transformer.
For small turbine starts generating power 12.6 kph (3.5 m/s) is the typical cut-in speed. At 36–54 kph (10–15 m/s) produces maximum generation power. At 90 kph (25 m/s) maximum, the turbine is stopped or braked.
Symmetrical breaking current: It is the rms value of a a.c component of the current in the pole at the instant of contact separation.
Asymmetrical breaking current: It is the rms value of the total current comprising the a.c and d.c components of the current in the pole at the instant of contact separation.
EXAMIANS