60 XLS140 Installation Manual Form Number 95-7673-3 P/N 51927:C  12/06/2005 
Applications NFPA 72-1999 Central or Remote Station Fire Alarm System (Protected Premises Unit)
4.2  NFPA 72-1999 Central or Remote Station Fire Alarm 
System (Protected Premises Unit) 
Figure 4.1 shows typical wiring diagram for a NFPA 72-1999 Central Station Fire Alarm System 
(Protected Premises Unit) or a Remote Station Fire Alarm System (Protected Premises Unit) using 
the Universal Digital Alarm Communicator/Transmitter (UDACT) and control panel. This 
provides typical wiring only; connect and program the UDACT according to the directions given in 
the UDACT Instruction Manual.
NOTE: An NFPA 72-1999 Central Station requires 24 hours of standby power; an 
NFPA 72-1999 Remote Station requires 60 hours of standby power.
NOTE: This application can also be done with the TM-4 Transmitter; refer to the Transmitter 
Module TM-4 document for more details.
TB13
EIA-485
+   ACS   –
24V NONRST     24V RESET
+        –          +
   
–
TB7
UDACT in ABS-8R
(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
nfs640-udact.cdr
Figure 4.1  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.