151
APPENDIX D
Wire Requirements
Connecting external system accessories to the main circuits must be carefully considered to ensure
proper operation. It is important to use the correct type of wire, gauge and run length for each
circuit. Reference the chart below to specify wire requirements and limitations for each circuit.
Table D.1 FACP Wire Specifications
CIRCUIT CONNECTIONS
WIRE REQUIREMENTS
Circuit Type
Circuit Function
Wire Type and Limitations
Recommended
Max. Distance
Feet (meters)
Wire Gauge
Initiating Device
Circuit
(power-limited)
Connects to
Initiating Devices
Untwisted, unshielded wire
(maximum loop resistance
not to exceed 100 ohms)
Distance limitation
set by 100 ohm
resistance limitation
12-18 AWG (3.25 - 0.75 mm
2
)
ANN-BUS
(EIA-485)
power-limited
Communication
for ANN-BUS
annunciator and
relay modules
Twisted pair a maximum
loop resistance of 120 ohms
6,000 (1,800 m)
12-18 AWG (3.25 - 0.75 mm
2
)
ANN-BUS
Power
Power for
ANN-BUS
annunciators
Refer to "ANN-BUS Devices" on page 37 for information on device wiring
24 VDC
Regulated,
resettable,
nonresettable
Power for
accessories and
4-wire devices
Untwisted, unshielded wire
Distance limitation
set by 4 volt
maximum line drop
12-18 AWG (3.25 - 0.75 mm
2
)
Auxiliary
Trouble Input
Open Collector
trouble input for
CHG-75,
CHG-120F, etc.
Single conductor
Distance limitation
20 feet in same
room
18 AWG (0.75 mm
2
)
Remote Sync
Output
Provides strobe
and normal sync
for remote NAC
power supplies
Untwisted, unshielded pair
wire
Distance set by 295
ohm resistance
limitation
12-18 AWG (3.25 - 0.75 mm
2
)
NAC Outputs
Connects to NAC
devices or Release
devices
Untwisted, unshielded pair
wire
Refer to Section D.1 and Section D.2 on page 152.
