dose any one know what is load factor for cable ampacity?

Answer 1

It is difficult to tell what you are asking for, but maybe this will help

http://www.interfacebus.com/Copper_Wire_AWG_SIze.html

Answer 2

Load factor is the estimated or measured average load for the circuit divided by the peak load for that circuit. If it is known that a cable has sufficient time to cool between application of loads, the size of the cable can sometimes be reduced safely.

Load factor regulations and calculation methods can be found in both the National Electric Code and National Electric Safety Code.