Specifications

RAM-300LCD Installation and Operation Manual
5
Wiring
To wire the RAM-300LCD, you must first remove the dead front plate. Wire from the last RAM-300LCD to the next
RAM-300LCD and so on; then from the first RAM-300LCD to the Fire Alarm Panel. There are only two connections
to be made, one for power and the RS-485 loop. Replace the dead front plate once all functional setup and wiring
is complete.
The RS-485 Wiring to the RAM-300LCD is recommended to be Twisted Shielded Pair.
The wire gauge may be
• 22 AWG up to 2000 ft.
• 20 AWG up to 4000 ft.
The 24V DC field wiring needs to be of an appropriate gauge for the number of annunciators and the total wiring run
length. See Current Drain for Battery Calculations on page 7 and calculate the Maximum current for all
annunciators summed together.
Note: All circuits are power limited and must use type FPL, FPLR or FPLP Power Limited Cable.
CAUTION: Accidentally connecting any of the 24V DC 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 m ft m ft m ft m Ohms
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