400 Amp Service Ground Wire Size. Be sure to brace, guy, or concrete service pole 8’ ground rod with approved ground rod clamp switch box conduit hot wire neutral lightning size size size size ground 400 amp 3” or 2 ½” 2 # 500mcm 1 # 250mcm 1#1/0 only copper wire (type thhn or thwn) allowed 16’ min. Minimum recommended earth conductor size in table b 5.1 is 25mm2 for 200a so make it 50mm2 for 400a maximum circuit length (out and back) is 84m for and hrc fuse and 60m for a type c mcb.

Making use of 600al top top a service with single main 400 amp ocpd is noncompliant even using the round up preeminence as 350 amp ocpds space available. 200 amp, 40 circuit panel 400 amp meter base 2x 4 back supports or 5/16 molly screws. Be sure to brace, guy, or concrete service pole 8’ ground rod with approved ground rod clamp switch box conduit hot wire neutral lightning size size size size ground 400 amp 3” or 2 ½” 2 # 500mcm 1 # 250mcm 1#1/0 only copper wire (type thhn or thwn) allowed 16’ min.