Non?Power-Limited Fire Alarm Circuit Conductors, and
Medium-Power Network-Powered Broadband Communications
Cables.
(A) General. Cables and conductors of Class 2 and Class 3
circuits shall not be placed in any cable, cable tray, compartment,
enclosure, manhole, outlet box, device box, raceway,
or similar fitting with conductors of electric light,
power, Class 1, non?power-limited fire alarm circuits, and
medium-power network-powered broadband communications
circuits unless permitted by 725.136(B) through (I).
(B) Separated by Barriers. Class 2 and Class 3 circuits
shall be permitted to be installed together with the conductors
of electric light, power, Class 1, non?power-limited fire alarm
and medium power network-powered broadband communications
circuits where they are separated by a barrier.
(C) Raceways Within Enclosures. In enclosures, Class 2
and Class 3 circuits shall be permitted to be installed in a
raceway to separate them from Class 1, non?power-limited
fire alarm and medium-power network-powered broadband
communications circuits.
(D) Associated Systems Within Enclosures. Class 2 and
Class 3 circuit conductors in compartments, enclosures, device
boxes, outlet boxes, or similar fittings shall be permitted to be
installed with electric light, power, Class 1, non?powerlimited
fire alarm, and medium-power network-powered
broadband communications circuits where they are introduced
solely to connect the equipment connected to Class 2 and
Class 3 circuits, and where (1) or (2) applies:
(1) The electric light, power, Class 1, non?power-limited fire
alarm, and medium-power network-powered broadband
communications circuit conductors are routed to maintain
a minimum of 6 mm (0.25 in.) separation from the conductors
and cables of Class 2 and Class 3 circuits.
(2) The circuit conductors operate at 150 volts or less to
ground and also comply with one of the following:
a. The Class 2 and Class 3 circuits are installed using
Type CL3, CL3R, or CL3P or permitted substitute
cables, provided these Class 3 cable conductors extending
beyond the jacket are separated by a minimum
of 6 mm (0.25 in.) or by a nonconductive sleeve or
nonconductive barrier from all other conductors.
b. The Class 2 and Class 3 circuit conductors are installed
as a Class 1 circuit in accordance with 725.41.
(E) Enclosures with Single Opening. Class 2 and Class 3
circuit conductors entering compartments, enclosures, device
boxes, outlet boxes, or similar fittings shall be permitted
to be installed with Class 1, non?power-limited fire
alarm and medium-power network-powered broadband
communications circuits where they are introduced solely
to connect the equipment connected to Class 2 and Class 3
circuits. Where Class 2 and Class 3 circuit conductors must
enter an enclosure that is provided with a single opening,
they shall be permitted to enter through a single fitting
(such as a tee), provided the conductors are separated from
the conductors of the other circuits by a continuous and
firmly fixed nonconductor, such as flexible tubing.
(F) Manholes. Underground Class 2 and Class 3 circuit conductors
in a manhole shall be permitted to be installed with
Class 1, non?power-limited fire alarm and medium-power
network-powered broadband communications circuits where
one of the following conditions is met:
(1) The electric light, power, Class 1, non?power-limited
fire alarm and medium-power network-powered broadband
communications circuit conductors are in a metalenclosed
cable or Type UF cable.
(2) The Class 2 and Class 3 circuit conductors are permanently
and effectively separated from the conductors of
other circuits by a continuous and firmly fixed nonconductor,
such as flexible tubing, in addition to the insulation
or covering on the wire.
(3) The Class 2 and Class 3 circuit conductors are permanently
and effectively separated from conductors of the
other circuits and securely fastened to racks, insulators,
or other approved supports.
(G) Cable Trays. Class 2 and Class 3 circuit conductors
shall be permitted to be installed in cable trays, where
the conductors of the electric light, Class 1, and non?
power-limited fire alarm circuits are separated by a solid
fixed barrier of a material compatible with the cable tray
or where the Class 2 or Class 3 circuits are installed in
Type MC cable.
(H) In Hoistways. In hoistways, Class 2 or Class 3 circuit
conductors shall be installed in rigid metal conduit, rigid
nonmetallic conduit, intermediate metal conduit, liquidtight
flexible nonmetallic conduit, or electrical metallic tubing.
For elevators or similar equipment, these conductors shall
be permitted to be installed as provided in 620.21.
(I) Other Applications. For other applications, conductors
of Class 2 and Class 3 circuits shall be separated by at least
50 mm (2 in.) from conductors of any electric light, power,
Class 1 non?power-limited fire alarm or medium power
network-powered broadband communications circuits unless
one of the following conditions is met:
(1) Either (a) all of the electric light, power, Class 1, non?
power-limited fire alarm and medium-power networkpowered
broadband communications circuit conductors
or (b) all of the Class 2 and Class 3 circuit conductors
are in a raceway or in metal-sheathed, metal-clad, non?
metallic-sheathed, or Type UF cables.
(2) All of the electric light, power, Class 1 non?power-limited
fire alarm, and medium-power network-powered broadband
communications circuit conductors are permanently
separated from all of the Class 2 and Class 3 circuit conductors
by a continuous and firmly fixed nonconductor,
such as porcelain tubes or flexible tubing, in addition to
the insulation on the conductors.
