A 115-kV transmission line has a positive sequence impedance of 28480 ohms (primary). a. You are...

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A 115-kV transmission line has a positive sequence impedance of 28480° ohms (primary). a. You are to set a Zone 1 mho-type phase distance (21-1) relay to cover 85% of the line and a Zone 2 (21-2) relay to cover 125% of the line. For better resistive fault coverage, the relay maximum reach angles are set to 60°. Determine the required relay reach settings (at the relay reach angle). Instrument transformer ratios are given as: CTR = 1200/5A and VTR = 1000/1V. b. Assuming a lagging power factor limit of 0.87, how much load (in primary MVA) can the Zone 2 relay carry at 1.0pu voltage? Don't worry about any additional safety margins or reduced voltage conditions. A 115-kV transmission line has a positive sequence impedance of 28480° ohms (primary). a. You are to set a Zone 1 mho-type phase distance (21-1) relay to cover 85% of the line and a Zone 2 (21-2) relay to cover 125% of the line. For better resistive fault coverage, the relay maximum reach angles are set to 60°. Determine the required relay reach settings (at the relay reach angle). Instrument transformer ratios are given as: CTR = 1200/5A and VTR = 1000/1V. b. Assuming a lagging power factor limit of 0.87, how much load (in primary MVA) can the Zone 2 relay carry at 1.0pu voltage? Don't worry about any additional safety margins or reduced voltage conditions.