Honeywell FIRE-LITE MS-10UD Series Manual page 36

Installation
The following formulas were used to generate the wire distance chart:
Maximum Resistance (Ohms)
Maximum Wire Length (feet)
(6,000 feet maximum)
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:
• 2 ANN-80 Remote Fire Annunciators
• 1 ANN-S/PG Serial/Parallel Printer Interface Module
• 1 ANN-I/O LED Driver Module
The total worst case current is calculated as follows:
ANN-80 Current Draw
ANN-S/PG Current Draw
ANN-I/O Current Draw
Total Worst Case Current Draw
Using this value and referring to the Wiring Distance Table 2.2 on page 35, it can be found that the available options are:
 463 feet maximum using 22 Gauge wire
 1,172 feet maximum using 18 Gauge wire
 1,866 feet maximum using 16 Gauge wire
 2,953 feet maximum using 14 Gauge wire
36
=
=
where: Rpu = Ohms per 1,000 feet for various Wire Gauges (see table below)
Wire Gauge
22
18
16
14
Wire Gauge
18
16
14
12
= 2 X 0.040 amps
= 1 X.0.040 amps
= 1 X.0.200 amps
6.0 Volts
Total Worst Case Current Draw (amps)
Maximum Resistance (Ohms)
Rpu
Ohms per 1,000 feet (Rpu)
16.2
6.4
4.02
2.54
Maximum Wire Length
312 feet
497 feet
787 feet
1,250 feet
= 0.080 amps
= 0.040 amps
= 0.200 amps
= 0.320 amps
MS-5UD & MS-10UD Series Manual — P/N 52626:C7 6/12/2018
ANN-BUS Devices
*500