Tables > Grounding > Conductors > Minimum size

	Rating Or Setting Of Automatic Overcurrent Device In Circuit Ahead Of Equipment, Conduit, Etc., Not Exceeding (Amperes) Size Copper Wire No. Aluminum Or Copper-Clad Aluminum Wire No. 15 14 12 20 12 10 30 10 8 40 10 8 60 10 8 100 8 6 200 6 4 300 4 2 400 3 1 500 2 1/0 600 1 2/0 800 1/0 3/0 1000 2/0 4/0 1200 3/0 250 kcmil 1600 4/0 350 kcmil 2000 250 kcmil 400 kcmil 2500 350 kcmil 600 kcmil 3000 400 kcmil 600 kcmil 4000 500 kcmil 800 kcmil 5000 700 kcmil 1200 kcmil 6000 800 kcmil 1200 kcmil
Where necessary to comply with Section 250-2(d), the equipment grounding conductor shall be sized larger than this table. *See installation restrictions in Section 250-120. Reprinted with permission from NFPA 70-1999, the National Electrical Code®, Copyright 1998, National Fire Protection Association, Quincy, MA 02269. This reprinted material is not the referenced subject which is represented only by the Standard in its entirety.
See also Guides Finding Voltage Drop for given conductor size Tables Minimum clearance of live parts Size data for hole saws