Table 3: Cable length guidelines for recommended wire sizes for low-voltage (<30 V) Inputs and
Outputs
Wire size/Gauge and type
Maximum cable length and
type
Assumptions
1.0 mm (18 AWG) stranded copper
457 m (1,500 ft) twisted wire
0.8 mm (20 AWG) stranded copper
297 m (975 ft) twisted wire
0.6 mm (22 AWG) stranded copper
183 m (600 ft) twisted wire
A
0.5 mm (24 AWG) stranded copper
107 m (350 ft) twisted wire
100 mV maximum voltage drop
Depending on cable and the
connected input or output device, you
may have to define an offset in the
setup software for the input or output
point.
1.0 mm (18 AWG) stranded copper
229 m (750 ft) twisted wire
0.8 mm (20 AWG) stranded copper
137 m (450 ft) twisted wire
0.6 mm (22 AWG) stranded copper
91 m (300 ft) twisted wire
B
0.5 mm (24 AWG) stranded copper
61 m (200 ft) twisted wire
100 mV maximum voltage drop
Depending on cable and the
connected input or output device, you
may have to define an offset in the
setup software for the input or output
point.
C
See Figure 8 to select wire size/gauge. Use
stranded copper wire
See Figure 8 to determine cable
length. Use twisted wire cable. N/A
Maximum cable length versus load
current
Use Figure 8 to estimate the maximum cable length
relative to the wire size and the load current (in mA)
when wiring inputs and outputs.
Note:
Figure 8 applies to low-voltage (<30 V)
inputs and outputs only.
Figure 8: Maximum wire length for low-voltage
(<30 V) Inputs and Outputs by current and wire
size
Communications bus and supply power
wiring guidelines
The provides information about the functions,
ratings, and requirements for the communication
bus and supply power terminals. The table also
provides guidelines for wire sizes, cable types, and
cable lengths for when you wire the controller's
communication buses and supply power.
Important:
Refer to the
N2 Modernization Guide
for Legacy N2 Controllers
for guidelines when
using this device on an N2 bus.
In addition, observe these guidelines when you wire
an SA bus and the 24 VAC supply power:
• Run all low-voltage wiring and cables separate
from high-voltage wiring.
• All SA bus cables, regardless of wire size, should
be twisted, insulated, stranded copper wire.
• Shielded cable is strongly recommended for all SA
bus cables.
• Refer to the
MS/TP Communications Bus
Technical Bulletin (LIT-12011034)
for detailed
information regarding wire size and cable length
requirements for SA buses.
Communications bus and supply power
terminal block
Note:
The SA Bus and FC Bus wiring
recommendations in this table are for MS/TP
bus communications at 38.4k baud. For more
information, refer to the
MS/TP Communications
Bus Technical Bulletin (LIT-12011034).
FAC3613 Advanced Application Field Equipment Controller Installation Guide
9
