300.11(C) Raceways Used as Means of Support. Raceways shall be
used only as a means of support for other raceways, cables, or
nonelectrical equipment under any of the following conditions:
(1) Where the raceway or means of support is identified as a
means of support
(2) Where the raceway contains power supply conductors for
electrically controlled equipment and is used to support
Class 2 circuit conductors or cables that are solely for the
purpose of connection to the equipment control circuits
(3) Where the raceway is used to support boxes or conduit
bodies in accordance with 314.23 or to support luminaires
in accordance with 410.36(E)