10
High-Speed NFN Manual —
P/N 54013:C4 8/8/2019
Section 3: Network Configurations
3.1 Point-to-Point Configuration
A point-to-point wiring configuration is defined as a segment with only two nodes/repeaters attached to it. In a point-to-point configura-
tion, two nodes/repeaters are interconnected by a single circuit that is terminated at each port (Refer to Figure 3.1 and Figure 3.3 for wir-
ing configurations).
Characteristic Impedance in a Point-to-Point Configuration
The wire segment of each point-to-point connection is a transmission line. The physical construction of the twisted-pair cable used for a
segment determines the characteristic impedance of that segment. To minimize unwanted data reflections, never mix more than one
brand name, gauge, or type of wire within a point-to-point segment.
3.2 NFPA Class B Configurations
High-Speed Noti•Fire•Net is capable of communicating using an NFPA Class B SLC (refer to Figure 3.1). Under this class of operation,
a single open, wire-to-wire short, wire-to-wire short and open, wire-to-wire short and ground, or open and ground results in fragmenta-
tion of the network. A single ground does not affect communication, but is detected. Each fragment of the network re-configures to per-
mit communication among the nodes within the fragment.
NOTE:
For 14 AWG (2.08 mm
2
) to 18 AWG (0.82 mm
2
) cable, the maximum allowable distance is 3,000 ft. (914.4 m) provided that the
maximum line DC Loop Resistance of 39 ohms is not exceeded.
A
B
A
B
A
B
A
B
A
B
A
B
A
B
A
B
Note: High-Speed Noti•Fire•Net network wiring
is power-limited.
NFPA Class B SLC
With Regeneration
(Point-to-Point Connections)
Network
Node
Network
Node
Network
Node
Network
Node
Network
Node
or
Repeater
Network
Node
Network
Node
or
Repeater
Network
Node
= Network Node or Repeater
with two ports, A and B
= Network Node
with two ports, A and B
= Cabinet or Conduit
Border
Figure 3.1 Class B Configurations