SilentKnight 5700 - Manual (Page 27)

Before You Begin Installing 151295
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.
3.6.4 Maximum Battery Standby Load
The table below shows the maximum battery standby load for the 5700 based on 24 and 60 hours of standby. The
standby load calculations of line D in the Current Draw Calculation Worksheet (Table 3-3) must be less than the
number shown in the table below 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).
Alarm/Standby: mA mA mA
B Auxiliary Devices Current
Notification Appliance Circuits Refer to device 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
18 AH 675 mA 250 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 the Current Calculation Worksheet to calculate the correct battery amperes/hour rating needed
for your installation.
Table 3-3: Current Calculation Worksheet for SD Devices
Device
# of
Devices
Current per Device
Standby
Current
Alarm
Current