FGCNYS 310.2.1 Bonding jumper. Where the electric service for the individual installation is 200 amperes or less, the bonding jumper shall not be smaller than 6 AWG copper wire or 4 AWG aluminum or copper-clad aluminum wire, and shall be permanently connected to the grounding electrode system. Where the electric service for the individual installation is more than 200 amperes, the bonding jumper shall be not smaller than the minimum grounding
electrode size determined in accordance with Table 250.66 of NFPA 70-2005 and sections 250.66(A) through 250.66(C) of NFPA 70-2005, and shall be permanently connected to the grounding electrode system.