Service Transformer and Indoor Disconnects

[Electriman]

Greetings,

I have a 3000A service 480 VAC. The utility pad mount transformer is located outside the building with no secondary over current protection.

I was wondering if my electrical room could be inside the building not near the perimeter walls. I am using the 6 disconnect switch rule. If so how far can I run the secondary cables before it terminate into disconnect switches?

 

[david luchini]

Greetings,

I have a 3000A service 480 VAC. The utility pad mount transformer is located outside the building with no secondary over current protection.

I was wondering if my electrical room could be inside the building not near the perimeter walls. I am using the 6 disconnect switch rule. If so how far can I run the secondary cables before it terminate into disconnect switches?

If you want the disconnecting means to be at a location not near the building exterior, the service conductors must be run under the building or encased in brick or concrete within the building, per NEC 230.6.

 

[augie47]

Once the raceway leaves the slab or encasement david noted in post 2, there is not exact length given. See 230.70(A)(2).
The allowed length is an AHJ call and often varies by area and specifics.