in any race- way, cable tray, or cable with conductors of any nonintrinsically safe circuit.
Exception No. 1: Where conductors of intrinsically safe circuits are separated from conductors of nonintrinsically safe circuits by a distance of at least 50 mm (2 in.) and secured, or by a grounded metal partition or an approved insulating partition.
FPN: No. 20 gauge sheet metal partitions 0.91 mm (0.0359 in.) or thicker are generally considered acceptable.
Exception No. 2: Where either (1) all of the intrinsically safe circuit conductors or (2) all of the nonintrinsically safe circuit conductors are in grounded metal-sheathed or metal-clad cables where the sheathing or cladding is capable of carrying fault current to ground.
FPN: Cables meeting the requirements of Articles 330 and 332 are typical of those considered acceptable.
Exception No. 3: Intrinsically safe circuits in a Division 2 or Zone 2 location shall be permitted to be installed in a raceway, cable tray, or cable along with nonincendive field wiring circuits when installed in accordance with
504.30(B).
Exception No. 4: Intrinsically safe circuits passing through a Division 2 or Zone 2 location to supply apparatus that is located in a Division 1, Zone 0 or Zone I location shall be permitted to be installed in a raceway, cable tray, or cable along with nonincendive field wiring circuits when installed in accordance with
504.30(B).
FPN: Nonincendive field wiring circuits are described in
501.10(B)(3), 502.10(B)(3), 503.10(B)(3), 505.15(C)(1)(g),
and 506.15(C)(7).
(2) Within Enclosures. Conductors of intrinsically safe circuits shall be separated from conductors of nonintrinsically safe circuits by one of the following means:
(1) Separation by at least 50 mm (2 in.) from conductors of any nonintrinsically safe circuits.
(2) Separation from conductors of nonintrinsically safe circuits by use of a grounded metal partition 0.91 mm (0.0359 in.) or thicker.
(3) Separation from conductors of nonintrinsically safe circuits by use of an approved insulating partition.
(4) Where either (1) all of the intrinsically safe circuit conductors or (2) all of the nonintrinsically safe circuit conductors are in grounded metal-sheathed or metal-clad cables where the sheathing or cladding is capable of carrying fault current to ground.
FPN: Cables meeting the requirements of Articles 330 and 332 are typical of those considered acceptable.
(5) All conductors shall be secured so that any conductor that might come loose from a terminal cannot come in contact with another terminal.
FPN No. 1: The use of separate wiring compartments for the intrinsically safe and nonintrinsically safe terminals is a typical method of complying with this requirement.
FPN No. 2: Physical barriers such as grounded metal partitions or approved insulating partitions or approved restricted access wiring ducts separated from other such ducts by at least 19 mm (3A in.) can be used to help ensure the required separation of the wiring.
(3) Other (Not in Raceway or Cable Tray Systems). Conductors and cables of intrinsically safe circuits run
in other than raceway or cable tray systems shall be
separated by at least 50 mm (2 in.) and secured from
conductors and cables of any nonintrinsically safe
circuits.