QUESTION-2: In the two-buses, one breaker arrangement shown in the figure left, initially S3, S5, B2, S6, S8, s10, B3 and S11 are closed Bus 1 S1 B1 S2 Bus 2 and the others are open. Make a list of operations required to: a) Take B3 out of service. b) Take Bus 2 out of service. without any service interruption in any feeders. S3 S4 S8 S9 S5 S10 B2 O B3 S6 S7 s1 S12

QUESTION-2: In the two-buses, one breaker arrangement shown in the figure left, initially S3, S5, B2, S6, S8, s10, B3 and S11 are closed Bus 1 S1 B1 S2 Bus 2 and the others are open. Make a list of operations required to: a) Take B3 out of service. b) Take Bus 2 out of service. without any service interruption in any feeders. S3 S4 S8 S9 S5 S10 B2 O B3 S6 S7 s1 S12

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter25: Surge, Spike, And Lightning Protection

Section: Chapter Questions

Problem 11RQ: In reference to the load, how are MOVs connected to help prevent voltage spikes and surges? Are MOVs...

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Figure 2 shows the circuit of a simple power system. The ratings of the generators, transformers and the motors are as shown in the figure. The reactance of lines 1 and 2 are 40 ohms and 50 ohms respectively. Assume that system is unloaded, and the generators are generating their rated voltage. Select the generator G₁ ratings as base values. Choose the fault location in bus 1, bus 2, or bus 3.( Only one bus location) And give this answer For a symmetrical three phase fault on the bus 1.Draw the reactance diagram for the fault with all the reactances marked in per unit. 2.Determine the Thevenin's equivalent circuit which can be used to calculate the fault current. (3) Calculate the fault current in ampere and fault power in MVA. (4) Calculate the fault current contribution from the generator connected to the bus for fault calculation.
(a) Write the junction rule for junction b. (b) write the loop rule for loop 1 (clockwise) and for loop 2 (clockwise).
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