Connecting old to new

[Toros]

Hi
i upgrading the old 200a, delta service to a 400A,delta by/with Square-D
what is the best thing to do/design
to reconnect one of the existing load, thought a sub panel located 40 feet away
in order to maintain series rating
(replacing the sub with Square-D or install set of special fuse @ 100k in the feeder ???)

tanx

 

[Ponchik]

Usually the EE does the SC calculations, don't they?

 

[hbendillo]

We are going to need some additional information. For instance, if you have an existing overhead service drop to a 200 amp disconnect on the exterior of the building, I would add another 200 amp disconnect and service mast next to the existing and have power company connect a new service drop to the existing and new disconnect. Then just feed a new 200 amp panel inside from the new disconnect.

How is the existing service set up? Overhead? Underground? Is there a service disconnect on the exterior of the building or is the service underground directly to a main panel in the building?