Fire-Lite MS-25E Addressable Fire Control Panel - Manual (Page 23)

Before You Begin Installing
53688 3-3
3.4 Wiring Specifications
Induced noise (transfer of electrical energy from one wire to another) can interfere with
telephone communication or cause false alarms. To avoid induced noise, follow these
guidelines:
• Isolate input wiring from high current output and power wiring. Do not pull one multi-
conductor cable for the entire panel. Instead, separate the wiring as follows:
• Do not pull wires from different groups through the same conduit. If you must run them
together, do so for as short a distance as possible or use shielded cable. Connect the shield
to earth ground at the panel. You must route high and low voltages separately.
• Route the wiring around the inside perimeter of the cabinet. It should not cross the circuit
board where it could induce noise into the sensitive microelectronics or pick up unwanted
RF noise from the high speed circuits. See Figure 3-1 for an example.
• 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 shield beads or by wrapping it
around a ferrite toroid.
Figure 3-1 Wire Routing Example
High voltage AC power Terminals
SLC loops Phone line circuits
Notification circuits NAC1 through NAC2
Relay circuits SBUS Wiring
1/4” spacing must
be maintained
between power
limited and Non-
power limited
wiring