AFP-400 Installation
PN
50253
:
A2 03/12/96
2-37
Calculating the Maximum Secondary Power Fire Alarm Current Draw
Use Table 2-3 to determine the maximum current requirements of second-
ary power source during fire alarm conditions. The total obtained in
Table 2-3 is the amount of current that the batteries must be capable of
supplying. Use this figure in Table 2-4 to determine the size of the batter-
ies needed for the fire alarm system.
Figures taken from Table 2-3 assume that, while in a fire alarm condition,
batteries must feed the main power supply (and any additional supplies
such as the AVPS-24 and AA-30) with the maximum rated power each
supply can provide.
On a system with a power supply having a small load, you can calculate
the exact alarm current requirements of the secondary supply. To do so,
add the secondary Non-Fire Alarm Load (from Table 2-2) to the total fire
alarm current draw of all Notification Appliances in the system. Use this
value in Table 2-4.
How to Use Table 2-3
Table 2-3
Maximum Secondary Power Fire Alarm Current Draw
Device
No. in Alarm
(Simultaneously)
Multiply
by
Current
(in amps)
Total Current/Type
MPS-400
1
X
6
AVPS-24
[ ]
X
3
AA-30
[ ]
X
3
AA-120
[ ]
X
7.3
Sum Column for Secondary Fire Alarm Load =
The Secondary Fire Alarm
Load cannot exceed the
following:
9.0 amps with PS-12120
batteries; and
12 amps with PS12250
or PS-12550 batteries.
