Cable ampacity and voltage drop

The easiest way to check is to deput a profesional consultant for detail calculation.

Please clarify the following:

1) cable copper or Aluminium

2) is it 2 runs of 120 sq.mm and one run of 70 sq.mm.

3) what will be power factor of the load.

4)If the sending end breaker is 800 Amps the receiving end breaker should also be 800 Amps.

2 runs of 120 sq.mm cable will not be adequate.

2 runs of 120 sq.mm copper will carry only 450 Amps laid in duct below ground.

2 runs of 150 sq.mm copper will carry only 520 Amps laid in duct below ground

2 runs of 120 sq.mm Aluminum will carry only 350 Amps laid in duct below ground.

2 runs of 150 sq.mm Aluminium will carry only 410 Amps laid in duct below ground

3 runs of 120 sq.mm Aluminum will carry only 510 Amps laid in duct below ground.

3 runs of 150 sq.mm Aluminium will carry only 615 Amps laid in duct below ground

May be ypu can choose 3 runs of 120 sq.mm Alu.cable or 2 runs of 140 sq.mm copper cable.

Voltage drop would be 3.8% for Aluminium cable and 3.2 % for copper cable.

For detailed calculations etc contact privately.