Honeywell SILENT KNIGHT Farenhyt Series Installation And Operation Manual page 16

Before You Begin Installing
These cases are marked in the chart with an asterisk (*). Maximum length can never
be more than 6,000 feet, regardless of gauge used. (The formula used to generate
this chart is shown in the note below).
Total Worst Case
Current Draw (amps)
0.100 1852 ft.
0.200 926 ft.
0.300 617 ft.
0.400 463 ft.
0.500 370 ft.
0.600 309 ft.
0.700 265 ft.
0.800 231 ft.
0.900 206 ft.
1.000 (Max) 185 ft.
Note: The following formulas were used to generate the wire distance chart:
Maximum Resistance (Ohms) =
Maximum Wire Length (Feet) =
(6000 feet maximum)
where: Rpu = Ohms per 1000 feet for various Wire Gauges (see table below)
Table 2-5: Wire Distances Per Wire Gauge
Wiring Distance: SBUS Modules to Panel
22 Gauge 18 Gauge
4688 ft.
2344 ft.
1563 ft.
1172 ft.
938 ft.
781 ft.
670 ft.
586 ft.
521 ft.
469 ft.
Total Worst Case Current Draw (amps)
Maximum Resistance (Ohms)
Table 2-6: Typical Wire Resistance Per 1000 ft.
Wire Gauge
22
18
16
14
2-8
16 Gauge
* 6000 ft.
3731 ft.
2488 ft.
1866 ft.
1493 ft.
1244 ft.
1066 ft.
933 ft.
829 ft.
746 ft.
6.0 Volts
Rpu
Ohms per 1000 feet (Rpu)
16.2
6.4
4.02
2.54
151153
14 Gauge
* 6000 ft.
5906 ft.
3937 ft.
2953 ft.
2362 ft.
1969 ft.
1687 ft.
1476 ft.
1312 ft.
1181 ft.
* 500