Wiring - Mircom RAM-300LCD Series Installation And Operation Manual

4.0

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 11 and
calculate the Maximum current for all annunciators summed together.
i
Note:
!
Attention: Accidentally connecting any of the 24V DC wires to the RS-485 wiring will
Table 4 Maximum Wiring Run to Last Annunciator
Max for all
Annunciators
Amperes ft
0.12 1180
0.30 470
0.60 235
0.90 156
1.20 118
1.50 94
1.70 78
All circuits are power limited and must use type FPL, FPLR or FPLP Power
Limited Cable.
result in damage to the Annunciator and/or to the Fire Alarm Control Panel to
which it is connected.
18AWG 16AWG
m ft m
360 1850 567
143 750 229
71 375 114
47 250 76
36 185 56
29 150 46
24 125 38
firealarmresources.com
14AWG 12AWG
ft m ft
3000 915 4250 1296
1200 366 1900 579
600 183 850 259
400 122 570 174
300 91 425 129
240 73 343 105
200 61 285 87
Max Loop
Resistance
m Ohms
15
6
3
2
1.5
1.2
1.0
9