subject electrical system in building

Question 1 a) List SIX (6) information needed to calculate the voltage drop in the wiring cable of electrical circuit. [3 marks] b) A 15hp single-phase motor is subjected to frequent stopping and starting. The cable supplies the motor via a two-core non-armoured cable having 90C thermosetting insulation and copper conductors, clipped direct. The ambient temperature is 60C. Determine: i The design current or full load current. The cross-sectional area of the conductor. [2 marks] [5 marks] ii. c) A three-phase circuit is run at 120 metre from MCCB to the load, clipped direct and not grouped with other circuits, in a multicore ammoured 70C PVC insulated cable having 95 mm copper conductors as in Figure 3. The design current and the ambient temperature of the circuit is 200 A and 45C respectively. The load power factor of the circuit is 0.8 lagging i. Determine the conductor operating temperature. [6 marks] ii. Determine the voltage drop in this circuit by considering conductor operating temperature [6 marks] 11. Calculate the percentage of the voltage drop. [3 marks] MCCB 0.8 p. 120m LOAD Figure 3 Question 1 a) List SIX (6) information needed to calculate the voltage drop in the wiring cable of electrical circuit. [3 marks] b) A 15hp single-phase motor is subjected to frequent stopping and starting. The cable supplies the motor via a two-core non-armoured cable having 90C thermosetting insulation and copper conductors, clipped direct. The ambient temperature is 60C. Determine: i The design current or full load current. The cross-sectional area of the conductor. [2 marks] [5 marks] ii. c) A three-phase circuit is run at 120 metre from MCCB to the load, clipped direct and not grouped with other circuits, in a multicore ammoured 70C PVC insulated cable having 95 mm copper conductors as in Figure 3. The design current and the ambient temperature of the circuit is 200 A and 45C respectively. The load power factor of the circuit is 0.8 lagging i. Determine the conductor operating temperature. [6 marks] ii. Determine the voltage drop in this circuit by considering conductor operating temperature [6 marks] 11. Calculate the percentage of the voltage drop. [3 marks] MCCB 0.8 p. 120m LOAD Figure 3