what size of wire is service wire is needed for a 200 amp panel copper size? aluminum size?
The smallest permitted would be 4/0 AL for a dwelling service
We use 3/0 copper for all 3. Lots of locals want that. Someone elce might know the code but I think NEC lets you go one smaller?
If we are talking dwelling unit services the NEC allows the use of Table 310.15(B)(6).
200 amp service 2/0 CU or 4/0 AL
100 amp service 4 CU or 2 AL
This does not apply to commercial services.
[This message has been edited by iwire (edited 09-25-2004).]