Fire-Lite MS-9200UDLSC Addressable Fire Alarm Control Panel - Manual (Page 43)

MS-9200UDLS Series Manual — P/N 52750:H 4/14/2014 43
Optional Module Installation Installation
The following formulas were used to generate the wire distance chart:
Exception: When using the ANN-RLY module, the installer must ensure that the maximum
24VDC power line drop does not exceed 0.3 volts. This results in the following wiring limitations:
Wiring Distance Calculation Example:
Suppose a system is configured with the following ANN-BUS modules:
• 3 ANN-80 Remote Fire Annunciators
• 1 ANN-S/PG Serial/Parallel Printer Interface Module
The total worst case current is calculated as follows:
Using this value and referring to the Wiring Distance Table 2.1 on page 42, it can be found that the
available options are:
 926 feet maximum using 22 Gauge wire
 2,344 feet maximum using 18 Gauge wire
 3,731 feet maximum using 16 Gauge wire
 5,906 feet maximum using 14 Gauge wire
Maximum Resistance (Ohms) =
6.0 Volts
Total Worst Case Current Draw (amps)
Maximum Wire Length (feet)
=
Maximum Resistance (Ohms)
*500
(6,000 feet maximum) Rpu
where: Rpu = Ohms per 1,000 feet for various Wire Gauges (see table below)
Wire Gauge Ohms per 1,000 feet (Rpu)
22 16.2
18 6.4
16 4.02
14 2.54
Wire Gauge Maximum Wire Length
18 312 feet
16 497 feet
14 787 feet
12 1,250 feet
ANN-80 Current Draw = 3 X 0.040 amps = 0.120 amps
ANN-S/PG Current Draw = 1 X.0.040 amps = 0.040 amps
Total Worst Case Current Draw = 0.160 amps