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(The similarity of the bus layout here for two CBs in each diameter to the 3-CB Mesh connection of a single feed should be noted as a path for augmentation from single feed to double feed connections.)

Mesh or Full Ring Bus (as 2 x 1.5 CB Diameters)

This arrangement provides a variation of providing future expansion as a full ring bus arrangement.  The substation is laid out as 2 x 1.5 CB Diameters with "bus connected" transformers. Initial expansion is by adding the indicated equipment and yet further expansion is achieved with additional 1.5 CB Diameters as per the previous system, or making the ring bigger.

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