Please use Canadian Electrical Code - 2018 and reference rules used.

Three 480/277 V panel boards are supplied with three sub-feeders A, B, and C. The load on A is 15 kVA with a pf of 1.0 (continuous); load B is 25 kVA with a pf of 0.95 (non-continuous); and load C is 35 kVA with pf of 0.9 (continuous). The three sub-feeders are supplied with a 75 feet long main feeder. The main feeder is 3-phase, 4-wire systems and all loads connected having less than 50% electric discharge type of lighting and there are no other loads that cause third harmonics. The allowance for voltage drop (phase to phase) is 1% for main feeder. Assume RW75 copper conductors installed in a steel conduit. Determine the size of the main feeder based on Ampacity and Voltage Drop. Hint: You need to determine the overall power factor to size main feeder based on voltage drop. Three 480/277 V panel boards are supplied with three sub-feeders A, B, and C. The load on A is 15 kVA with a pf of 1.0 (continuous); load B is 25 kVA with a pf of 0.95 (non-continuous); and load C is 35 kVA with pf of 0.9 (continuous). The three sub-feeders are supplied with a 75 feet long main feeder. The main feeder is 3-phase, 4-wire systems and all loads connected having less than 50% electric discharge type of lighting and there are no other loads that cause third harmonics. The allowance for voltage drop (phase to phase) is 1% for main feeder. Assume RW75 copper conductors installed in a steel conduit. Determine the size of the main feeder based on Ampacity and Voltage Drop. Hint: You need to determine the overall power factor to size main feeder based on voltage drop