314.28(E) Raceway Supported Enclosure, Without Devices, Luminaires (Fixtures), or Lampholders. An enclosure that does not contain a device(s) other than splicing devices or support a luminaire(s) [fixture(s)], lampholder, or other equipment and is supported by entering raceways shall not exceed 1650 cm3 (100 in.3) in size. It shall have threaded entries or have hubs identified for the purpose. It shall be supported by two or more conduits threaded wrenchtight into the enclosure or hubs. Each conduit shall be secured within 900 mm (3 ft) of the enclosure, or within 450 mm (18 in.) of the enclosure if all conduit entries are on the same side.
Exception: Rigid metal, intermediate metal, or rigid nonmetallic conduit or electrical metallic tubing shall be permitted to support a conduit body of any size, including a conduit body constructed with only one conduit entry, provided the trade size of the conduit body is not larger than the largest trade size of the conduit or electrical metallic tubing.
handbook commentary
Boxes are not permitted to be supported by rigid raceways using locknuts and bushings. Enclosures without devices or luminaires, however, are considered to be adequately supported, provided the conduit is connected to the enclosure by threaded hubs and the threaded conduits enter the box on two or more sides and are supported within 3 ft of the enclosure. A box is not permitted to be supported by a single raceway.
[This message has been edited by gfretwell (edited 09-06-2005).]
[This message has been edited by gfretwell (edited 09-06-2005).]
