What is the basic phenomenon to use cable 4 motors 4 eg:- a 22Kw or 30 Hp motor which size of cable is used in Cu or Al & in which core and why??

Hi I think ,you need to know /phase current of motor.on basics of current select cable acc to electrical standards.

Motor full load amps (fla) is 40 ampere. Accordingly refer to the cable catalogue and select considering factors like temperature, length, grouping of cables in cable tray for derating of the current carrying capacity of the cable. Appearantly, you need 25 sq. Mm. Copper cable or 35 sq.mm. Aluminium cable. (more excessive size cable lugs even will not get accommodated at the terminals of motor itself.)