User Manual

Before You Begin Installing 151274-L8
3-10
1. Total does not include isolator devices or accessory bases.
2. If using 24 VDC aux power only. No standby or alarm current for battery calculation if using 24 VAC, 120
VAC or 240 VAC.
3. If using door holders, you do not need to consider door holder current for alarm/battery standby, because
power is removed during that time. However, during normal operation, door holders draw current and must
be included in the 6.0A total current that can be drawn from the panel.
4. Use next size battery with capacity greater than required.
5. The FACP can only support 5 devices w/LED’s on. This current draw has been added to the panels alarm
current.
3.6.1.3 Maximum Battery Standby Load
The table below shows the maximum battery standby load for the 5808 based on 24 and 60 hours of standby. The
standby load calculations of line D in the Current Draw Calculation Worksheet (Table 3-2 for SK devices and
Table 3-3 for SD devices) must be less than the number shown in the Table 3-4 for the battery size used and
standby hours required.
* Required for NFPA 72 Auxiliary Protected Fire Alarm systems for Fire Alarm Service (City Box) and Remote
Station Protected Fire Alarm systems (Polarity Reversal) and Digital Alarm Communicator/Transmitter
(DACT).
Notification Appliance Circuits Refer to devices manual for current rating.
Alarm: mA
mA
Alarm: mA
mA
Alarm: mA
mA
Alarm: mA
mA
C Notification Appliances Current
mA
D Total current ratings of all devices in system (line A + line B + C) mA mA
E Total current ratings converted to amperes (line D x .001): A A
F Number of standby hours (24 or 60 for NFPA 72, chapter 1, 1-5.2.5): H
G Multiply lines E and F. Total standby AH AH
H Alarm sounding period in hours. (For example, 5 minutes =.0833 hours) H
I Multiply lines E and H. Total alarm AH
AH
J
Add lines G and I.
4
Total ampere hours
required
AH
Table 3-4: Maximum Battery Standby Load
Rechargeable Battery Size
Max. Load for 24 hrs.
Standby, 5 mins. Alarm
*Max. Load for 60 hrs.
Standby, 5 mins. Alarm
7 AH 221 mA 85 mA
12 AH 475 mA 190 mA
18 AH 685 mA 270 mA
35 AH 1.1 A 450 mA
Warning!
Silent Knight does not support the use of batteries smaller than those listed in table above. If you use a battery too small for
the installation, the system could overload the battery resulting in the installation having less than the required 24 hours
standby power. Use Table 3-4 to calculate the correct battery amperes/hour rating needed for your installation.
Table 3-3: Current Draw worksheet for SD Devices
Device
Number of
Devices
Current per Device
Standby
Current
Alarm
Current