I need to know what is the allowed reduction of parallel conductors to still meet the requirements of the load? If you use parallel conductors does each conductor have to be rated to 80% of full load current? On a service entrace that I am workig on, the existing SEC's are 4/0 aluminum in parallel (RWH 4/0 compact to be exact). It's a 3 phase system and max amps is 208 from the transformer. I know I can use 4/0 copper and just run 3 line conductors and 1 neutral, why didn't they? Cost? It would be easier to pull the 4 coppers instead of the 8 aluminums. What is the deciding factor? Thanks!
