Fire-Lite MS-25E Addressable Fire Control Panel - Manual (Page 25)

Before You Begin Installing
53688 3-5
3.6 Calculating Current Draw and Standby Battery
This section is for helping you determine the current draw and standby battery requirements
(Table 3-2).
3.6.1 Worksheet Requirements
The following steps must be taken when determining MS-25 current draw and standby battery
requirements.
1. For the MS-25, the worst case current draw is listed for the panel and all addressable
devices. Fill in the number of addressable devices that will be used in the system and com-
pute the current draw requirements for alarm and standby. Record this information in the
Current Calculation Worksheet at Line A.
2. Add up the current draw for all auxiliary devices and record in the table at Line B.
3. Add up all notification appliance loads and record in the table at Line C.
4. For notification appliance circuits and auxiliary devices not mentioned in the manual,
refer to the device manual for the current ratings.
5. Make sure that the total alarm current you calculated, including current for the panel itself,
does not exceed 2.0 A. This is the maximum alarm current for the MS-25 control panel.
If the current is above 2.0 A you will need to use a notification power expander(s) such as
the Fire-Lite FCPS-24FS6 (8) power supply to distribute the power loads so that the MS-
25 or the power expanders do not exceed their power rating.
6. Complete the remaining instructions in the Current Calculation Worksheet for determining
battery size requirements.