50
NFS2-640/E Installation Manual —
P/N 52741:P2 7/10/14
Applications
NFPA 72 Central or Remote Station Fire Alarm System (Protected Premises Unit)
UDACT in ABS-8RB
(shown with cover removed)
Solid earth
ground
To supervised
phone lines
Ferrite cores
P/N 29090
FACP Cabinet
EIA-485
(ACS Mode)
24 VDC
Nonresettable power
Supervised and power-limited
EIA-485 and power wiring
CPU
2-6
4
0-u
d
act
.w
mf
Figure 4.2 Typical Wiring Diagram for a Central Station Fire Alarm System
NOTE:
Install a UL-listed 120 ohm End-of-Line resistor (P/N 71244) UDACT TB1 terminals 3
and 4 if this is the last or only device on EIA-485 line.