MGVCL Exam Paper (30-07-2021 Shift 2) The Great Barrier Reef is located in which country? Germany Canada Australia India Germany Canada Australia India ANSWER DOWNLOAD EXAMIANS APP
MGVCL Exam Paper (30-07-2021 Shift 2) A three-phase, 12 kV, 50 Hz and 300 kW load is operating at 0.8 pf lag. If the pf is to be improved to unity, using star connected capacitor, the per phase value of the reactive VAR required is: 75 kVAR 100 kVAR 25 kVAR 50 kVAR 75 kVAR 100 kVAR 25 kVAR 50 kVAR ANSWER EXPLANATION DOWNLOAD EXAMIANS APP The reactive VAR required = kW*(tanφ1 -tanφ2)Cosφ1 = 0.8φ1 = 36.87 deg.Cosφ2 = 0φ2 = 0 deg.kVAR required = kW*(tan(36.87) - tan(0))= 300*1000(0.75)= 225.00 kVARPer phase value = 225.00/3= 75 kVAR
MGVCL Exam Paper (30-07-2021 Shift 2) The expression for voltage regulation of a short transmission line for leading power factor is given by: ____, where, 'I' is the line current, 'V_r' is the receiving end voltage, 'R' is the line resitance and 'X' is the line reactance. (IRcosφ_r + IXsinφ_r)/V_r (IRcosφ_r - IXsinφ_r)/V_r (IXcosφ_r + IRsinφ_r)/V_r (IXcosφ_r - IRsinφ_r)/V_r (IRcosφ_r + IXsinφ_r)/V_r (IRcosφ_r - IXsinφ_r)/V_r (IXcosφ_r + IRsinφ_r)/V_r (IXcosφ_r - IRsinφ_r)/V_r ANSWER EXPLANATION DOWNLOAD EXAMIANS APP For lagging power factor = (IR*cosφ + IXsinφ)/V_rFor leading power factor = (IR*cosφ - IXsinφ)/V_rZero voltage regulation occurs on leading power factor only.
MGVCL Exam Paper (30-07-2021 Shift 2) A 3-phase motor load has a p.f. of 0.397 lagging. The two wattmeter method used to measure power show the input as 30 kW. Find the reading on each wattmeter. W1 = -5 kW and W2 = 35 kW W1 = 10 kW and W2 = 20 kW W1 = -10 kW and W2 = 40 kW W1 = 5 kW and W2 = 25 kW W1 = -5 kW and W2 = 35 kW W1 = 10 kW and W2 = 20 kW W1 = -10 kW and W2 = 40 kW W1 = 5 kW and W2 = 25 kW ANSWER EXPLANATION DOWNLOAD EXAMIANS APP Here,Cosφ = 0.397P = 30 kW = √3*V_L*I_L*cosφV_L*I_L = 30kW/(√3*0.397) = 43628.48 VAReadings of wattmeter W1 = V_L*I_L*cos(30+φ)Readings of wattmeter W2 = V_L*I_L*cos(30-φ)
MGVCL Exam Paper (30-07-2021 Shift 2) Which one of the following statement is TRUE? In the cables, the location of fault is usually found out by comparing the capacitances of insulated conductors. In the cables, sheaths are used to provide enough strength. The current carrying capacity of cables in DC is less than that in AC. Underground cables are laid at sufficient depth to avoid being unearthed easily due to removal of soil. In the cables, the location of fault is usually found out by comparing the capacitances of insulated conductors. In the cables, sheaths are used to provide enough strength. The current carrying capacity of cables in DC is less than that in AC. Underground cables are laid at sufficient depth to avoid being unearthed easily due to removal of soil. ANSWER EXPLANATION DOWNLOAD EXAMIANS APP In the cables, the location of fault is usually found out by comparing the capacitances of insulated conductors.
MGVCL Exam Paper (30-07-2021 Shift 2) If all the devices are connected to a central hub, then the topology is called Bus Topology Tree Topology Star Topology Tree Topology Bus Topology Tree Topology Star Topology Tree Topology ANSWER DOWNLOAD EXAMIANS APP
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