What size of ground is required for a 400 amp service?

Answer by  deli (32)

If your dealing with panel box,it would be 3awg copper or 1awg aluminum. But it also varies on the distance on which your wire is being ran. Now if your talking ground rods,It depends on the facility and buildings you have. The code varies from state to state.

Answer by  joemason (83)

The minimum size of ground for a 400 amp service with one set of feeders, utilizing copper-will be a 1/0 copper ground.

Answer by  lftmx3 (39)

According to the 2008 national electrical code book you will need at least 3 AWG copper wire or 1 AWG aluminum wire. Make sure you do not need to splice the ground connection anywhere because this will de-rate the wire and violate electrical code. Be certain that any lugs or ring terminals are properly sized as well.

Answer by  Anonymous

according to the NEC 2005 edition table 250.122 minimum size Equipment Grounding Conductors for Grounding Raceway and Equipment # 3AWG Copper is the correct Size for a 400 amp service or # 1 AWG Aluminum