Can someone help me grab the concept of this 320 amp service debacle. From what I understand a 400 amp meter socket is actually a 320amp meter socket because of the 80% rating. So is a 400 amp load enter only rated for 320 amps? On our parts we need to ct meter a 400 amp service. But we can use a 320amp meter sockets for other installations. :? Is it only a true 400 amp service if it's ct metered