Any other thoughts?
Any other thoughts?
I am looking at a set of plans for a home and a detached garage. The owners want an apartment above the garage on a separate meter. My plan is to wire the garage on that meter however I was curious if we could feed the building with a feeder from the house and have a service for the apartment. IMO, it is compliant. 225 says one feeder and that is what I have- I also have one service so I don't see an issue. Anyone see a problem? Of course I would group the discos.
This is actually pretty interesting (ignoring the zoning issue).
230.2 Number of Services. A building or other structure served shall be supplied by only one service unless permitted in 230.2(A) through (D).
230.2 (B) Special Occupancies. By special permission, additional services shall be permitted for either of the following:
(1) Multiple-occupancy buildings where there is no available space for service equipment accessible to all occupants
230.2 (E) Identification. Where a building or structure is supplied by more than one service, or any combination of branch circuits, feeders, and services, a permanent plaque or directory shall be installed at each service disconnect location denoting all other services, feeders, and branch circuits supplying that building or structure and the area served by each. See 225.37.
225.37 Identification. Where a building or structure has any combination of feeders, branch circuits, or services passing through it or supplying it, a permanent plaque or directory shall be installed at each feeder and branch-circuit disconnect location denoting all other services, feeders, or branch circuits supplying that building or structure or passing through that building or structure and the area served by each.
225.37 Exception No. 2: This identification shall not be required for branch circuits installed from a dwelling unit to a second building or structure.
The two requirements essentially say the same thing,
I think, it would be nice if they used the same words. I'd probably ignore the exception and put a plaque up any away.
Now the service at the garage/apartment needs to meet all the requirements for grounding and the feeder/branch circuit from the other building needs to meet all its grounding requirements.
If we use ground rod(s) at the home and at the garage/apartment building, we can connect the two with #6 AWG copper wire and treat the rod(s) at each other building as supplemental grounds. The #6 can also serve as the grounding connection between the home and garage. (The wire would need to be larger if the GEC for the feeder size requires it.)
I would mount the apartment service disconnect and the garage feeder/branch circuit disconnect adjacent to each other and interconnect the four grounding wires (from rod(s), from feeder, to service and feeder disconnects). I would interconnect the grounding and neutral only in the service disconnect.