Service Conduit/Conductors Mounted on Face of Building

[NTambo]

In a scenario where a new service is being installed on an upper floor (2nd or 3rd) of an existing structure like a parking garage, would service conduit/conductors from a pad-mounted transformer mounted on the exterior face of the building count as being "inside" the building for the purposes of 230.70(A)(1)?

My understanding of 230.70 is that the intent is to limit the unprotected service conductor run to mitigate the risk of fire. It seems to me that service conductors mounted on the exterior face of the building would present a similar risk level as service conductors mounted on the same all but on the interior side, but I was not able to find anything in the NEC that clarified the situation.

 

[david luchini]

In a scenario where a new service is being installed on an upper floor (2nd or 3rd) of an existing structure like a parking garage, would service conduit/conductors from a pad-mounted transformer mounted on the exterior face of the building count as being "inside" the building for the purposes of 230.70(A)(1)?

My understanding of 230.70 is that the intent is to limit the unprotected service conductor run to mitigate the risk of fire. It seems to me that service conductors mounted on the exterior face of the building would present a similar risk level as service conductors mounted on the same all but on the interior side, but I was not able to find anything in the NEC that clarified the situation.

Those conductors would be outside the building.

 

[NTambo]

Thanks for the response. Do you have any examples or references that would support that? I'm trying to wrap my head around why that would be the case. Since the unprotected conductors would be mounted on the face of the building, I could see a scenario where an inspector/AHJ would view the unprotected conductors as a fire risk and require a service entrance disconnect at ground level.

 

[david luchini]

Thanks for the response. Do you have any examples or references that would support that? I'm trying to wrap my head around why that would be the case. Since the unprotected conductors would be mounted on the face of the building, I could see a scenario where an inspector/AHJ would view the unprotected conductors as a fire risk and require a service entrance disconnect at ground level.

I don't think you will find a reference that says items outside the building are considered to be outside the building. I would think the fact that they are literally outside the building would support that.

The disconnecting means has to be inside the building nearest the point of entrance of the conductors to satisfy 230.70(A)(1).

 

[LarryFine]

Do you have any examples or references that would support that?

Almost every service in America.

 

[don_resqcapt19]

Where is the service equipment for the other occupancies in that building located?

 

[NTambo]

Where is the service equipment for the other occupancies in that building located?

In an existing electrical room on the first floor of the building. The new service is 3000A 480/277V so the capacity required the installation of an additional service.

 

[don_resqcapt19]

In an existing electrical room on the first floor of the building. The new service is 3000A 480/277V so the capacity required the installation of an additional service.

So with that large of service the code does permit more than one service. There is no code issue running the service conductors up the outside of surface the building. Some local fire and building codes do have restrictions on the access to the service equipment, but it is fine with the NEC as long as the service disconnect is located nearest the point of entry of the service conductors.
The code does not define any set distance as being nearest the point of entry. I read "nearest" as meaning exactly that...you come through the wall and either directly into the service equipment or directly up or down into the service equipment. Some areas, like mine, have local amendments setting a maximum length of the service conductors inside the building....our local code sets that at ten feet.

 

[NTambo]

The code does not define any set distance as being nearest the point of entry. I read "nearest" as meaning exactly that...you come through the wall and either directly into the service equipment or directly up or down into the service equipment. Some areas, like mine, have local amendments setting a maximum length of the service conductors inside the building....our local code sets that at ten feet.

This part makes sense to me. An engineer that I know suggested that conductors mounted on the exterior wall should be considered inside the building, so I wanted to get some additional opinions and see if anyone had run into that before.

 

[Eddie702]

Conductor on the outside of the building are considered....................... outside the building. You can run the service conductor all the way around the building on the outside if you want.