SilentKnight SKE-450 Voice Evacuation Control Panel - Manual (Page 19)

Installation
151267 3-9
3.4.2 Wiring Specifications
The maximum line resistance of the wire run from FACP to voice evacuation control system is
50W. All wiring and devices installed in the system must meet the standards described in
National Electrical Code (NFPA 70), NFPA Standard 72, and Life Safety Code (NFPA 101).
To avoid induced noise (transfer of electrical energy from one wire to another), keep input
wiring isolated from high-current output and power wiring. Avoid pulling one multiconductor
cable for the entire panel. Instead, separate the wiring as follows:
DO NOT pull wires from different groups through the same conduit.
For the same reasons, wiring within the cabinet should be routed around the perimeter of the
cabinet. It should not cross the printed circuit board where it could induce noise into the
sensitive microelectronics or pick up unwanted RF noise from the high speed circuits.
High frequency noise, such as that produced by the inductive reactance of a speaker or bell,
can also be reduced by running the wire through ferrite beads or by wrapping it around a
ferrite toroid core. Figure 3-5 provides an example.
Figure 3-5 Wire Routing Example
Table 3-6
1/4" spacing must be maintained Input/Output Type Wiring
between each of these circuit types; Non Power-Limited: AC power, Standby batteries
as well as between power limited Power-Limited: Notification devices, SKE-SRM, and Relays
and non power-limited circuits. Audio: Speaker
Speaker
Speaker To AC
CMD Inputs
Battery Cable