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Semester 2, 2021/22 Subject Code: EE3009C Question 4 For the single-phase 220 V AC electrical distribution installation shown in Figure Q4, the fuse on the outgoing way from the rising main is a BS88 gG HBC fuse of 200 A, while the 2 MCBs on the 2 outgoing ways of the floor distribution board are 63 A Type B MCBs. The resistance of the circuit from the fuse to each of the MCB is (0.1+ a/100) 12, while the resistance of each circuit from each of the MCB to its respective load is (0.3 + b/100) 12. The resistance between the voltage source to the fuse is zero, and the resistances of the fuse and the 2 MCBs are also zero. Determine whether the system can provide selectivity for a solid short-circuit fault between line and neutral, if the fault is occurring anywhere along the circuit of one of the 2 outgoing ways of the floor distribution board. Show your calculation steps clearly. (5 marks) (1 mark) If selectivity is not achieved, what should be done? IE Rising Main