5
Wiring Instructions
5.0 Wiring Instructions
RS-485 Wiring
24 VDC
INPUT
-
+
-
+
24 VDC
OUTPUT
24 VDC POWER FROM FIRE ALARM MAIN BOARD
OR PREVIOUS ANNUNCIATOR
24 VDC POWER TO
NEXT ANNUNCIATOR
+
-
S
S
-
+
RS-485
INPUT
RS-485
OUTPUT
RS-485 TO NEXT ANNUNCIATOR
(TWISTED SHIELDED PAIR)
RS-485 FROM FIRE ALARM MAIN BOARD OR PREVIOUS
ANNUNCIATOR (TWISTED SHIELDED PAIR)
RAXN-LCDG
ALL CIRCUITS ARE POWER LIMITED
AND MUST USE TYPE FPL, FPLR, OR
FPLP POWER LIMITED CABLE
The RS-485 wiring to the
RAXN-LCD Display Module
is recommended to be
twisted shielded pair as
shown in the diagram to the
right. The RS-485 wire
gauge may be:
• 22 AWG up to 2000 ft.
• 20 AWG up to 4000 ft.
The RS-485 wiring from the
fire alarm control panel to
the annunciator(s) must be
point-to-point from the fire
alarm panel to the first
annunciator, then to the next
annunciator, and so on. No
star wiring or T-tapping is
allowed.
Each RAXN-LCD Shared
Display has a 120 ohm end-
of-line resistor on its RS-485
output terminals. This
resistor is removed on all except the last wired annunciator.
24V DC Wiring
The 24 VDC field wiring needs to be of an appropriate gauge for the number of annunciators
and the total wiring run length. Refer to the Current Drain for Battery Calculations on page 8
to calculate the maximum current for all annunciators summed together.
Accidentally connecting any of the 24 VDC wires to the RS-485 wiring will result in damage to
the annunciator and/or to the fire alarm control panel to which it is connected.
Total Maximum
Current for all
Annunciators
Maximum Wiring Run to Last Annunciator Max. Loop
Resistance
18AWG 16AWG 14AWG 12AWG
Amperes ft mft mft mft mOhms
0.12 1180 360 1850 567 3000 915 4250 1296 15
0.30 470 143 750 229 1200 366 1900 579 6
0.60 235 71 375 114 600 183 850 259 3
0.90 156 47 250 76 400 122 570 174 2
1.20 118 36 185 56 300 91 425 129 1.5
1.50 94 29 150 46 240 73 343 105 1.2
1.70 78 24 125 38 200 61 285 87 1.0
