Master 66 stated it was 4/0 SER in PVC. I agree USE would and should be acceptable as it has no jacket.
Roger I couldn't agree more about SER cable not being a raceway, unless of course an inspector tells you the definition states
"an enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables or etc." and he considers SE to meet that definition. The way it has been explained to me around here, if it is jacketed it is considered a raceway. NOT my definition but what I have to live with.
