What is a gutter

[John Cahill]

What is definition of a gutter in NEC terms? Where are they used. Is conduit a gutter? Thanks

[Greg Fretwell]

It is a <usually> metal trough with a removable cover typically connecting 2 cabinets but it might be a stand alone assembly

[jtedesco1]

This is where the term is used:

312.6 Deflection of Conductors

Table 312.6(A) Minimum Wire-Bending Space at Terminals and Minimum Width of Wiring Gutters

The definition of Raceway:

Raceway. An enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables, or busbars, with additional functions as permitted in this Code.

Raceways include, but are not limited to, rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, liquidtight flexible conduit, flexible metallic tubing, flexible metal conduit, electrical nonmetallic tubing, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways "TROUGHS", and busways.

The term "Gutter" is used in this non raceway location in the NEC:

ARTICLE 366 Auxiliary Gutters
I. General
366.1 Scope.
This article covers the use, installation, and construction requirements of metal auxiliary gutters and nonmetallic auxiliary gutters and associated fittings.
366.2 Definitions.
Metallic Auxiliary Gutter. A sheet metal enclosure used to supplement wiring spaces at meter centers, distribution centers, switchboards, and similar points of wiring systems. The enclosure has hinged or removable covers for housing and protecting electrical wires, cable, and busbars. The enclosure is designed for conductors to be laid or set in place after the enclosures have been installed as a complete system.
Nonmetallic Auxiliary Gutter. A flame retardant, nonmetallic enclosure used to supplement wiring spaces at meter centers, distribution centers, switchboards, and similar points of wiring systems. The enclosure has hinged or removable covers for housing and protecting electrical wires, cable, and busbars. The enclosure is designed for conductors to be laid or set in place after the enclosures have been installed as a complete system.

For the Commercial Inspector this expands on the need for this information.