Hi everybody...
I replaced two 2-2-2-4 SER with 2/0-2/0-2/0-4 & 1/0-1/0-1/0-4 to get 125A in each unit for a two-family. The upstairs SER was de-rated for attic heat & length. I have a 2 gang Siemens WP2211RJ gang meter and a 200A panel (P4040B1200CU) back fed with a 125A breaker and a 125A lug...