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D3. A 380V 3-phase 20kW sewage pump runs at power factor of 0.9 and efficiency of 0.93. It is connected to the power source by a 4-core armoured XLPE insulated copper cable. The cable is installed in touching with one other similar circuit on a perforated cable tray at an ambient temperature of 35°C. MCCB of 30, 40, 50 and 63A can be selected as overcurrent protective device. The length of the cable is 60m. The allowable voltage drop is within 4%. And copper loss of the circuit should be within 2.5%. (a) Determine the full load current of the motor. (b) Determine the most suitable rating of MCCB for protection. (C) Determine the minimum size of supply cable for the motor circuit. (Refer to Appendixes 2, 3 and 4.) (5 marks) (3 marks) (12 marks)