service upgrade

[ceb58]

I have the answer from the head inspector but would like to see what your call is. This is a job I am looking at to bid.
Home has 200amp service (back to back) They are doing another addition which will throw the calculation over 200. Here is the plan. 200 meter base is between the garage door and a window in garage. I plan on installing a 400 meter base on an adjacent wall that comes out at 90 deg. From the new base I will pipe over and 90 back toward the old base. Remove the old base and install a J box and splice onto the existing 4/0 alu. seu. On the other side of the 400amp I will install a 125amp disco run down and into basement with ser for a new sub panel. My question to the inspector was would he allow the existing 4/0 seu to stay keeping the 200amp rating or would I have to tear it out to the panel and replace with large seu. How would you call it?

 

[LarryFine]

How would you call it?

Which code, and what's the present load?

I'd replace it anyway to avoid the splice and J-box. You'd save 3 or 4 feet of cable?

Added: What about grouped mains? Wouldn't you need two disco's?

 

[augie47]

From what I read, I have the same questions as Larry. (1) It doesn't sound like your service disconnects are grouped, (2) if you run all the way to the J box, why not continue to the panel if they are back to back.

 

[ceb58]

Which code, and what's the present load?

I'd replace it anyway to avoid the splice and J-box. You'd save 3 or 4 feet of cable?

Added: What about grouped mains? Wouldn't you need two disco's?

Under 2008 code. Present load calculation is around 160 amps. House has been added onto before with out any load consideration. 200 amp panel is FULL.
The home is nice brick and, I know its hard to imagine, some one has built a work bench/ shelf under and over the panel. The way it looks is the seu comes in to a stud cavity turns into another cavity then turns again to the cavity the panel is in. If I were to put a 200 amp disco then I would have to replace it with 300mcm al SER all the way to panel. My pipe would be on the exterior to the j box so the closest point of entry would be the same as it is now. Bottom line is I am trying to keep from having the Sheetrock removed. I will let the inspector deal with the bench/shelving when the time comes.
For what its worth the inspector said he had no problem with what I proposed and would still consider the 4/0 al. good at 200amp since it was existing before 2008 code.