Earthing of a system is to protect the system from high surge current/voltage due to lighening while neutral provides return path to the current flowing in the tranmission line.
Cable selection not only depends on the load current but also depends on Temperature, Length (Distance between LT Switchgear MCC/PMCC to Motor). If load is increase then current will also increase if ...
raju
Apr 6th, 2012
Voltage is directly proportional length, current is proportional to area of cross section of the wire.