LS10144-001SK-E
Before You Begin Installation
3-12
1. The FACP can only support 5 devices w/LED’s on. This current draw has been added to the panels alarm current.
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. Total does not include isolator devices or accessory bases.
3.7.4
Maximum Battery Standby Load
Table 3-4 and Table 3-5 show the standby load calculations for the 6820 / 6820EVS based on 24 and 90 hours of
standby. The standby load calculations of line D in the Current Draw Calculation Worksheet must be less than
the number shown in Table 3-4 and Table 3-5 for the selected battery size, standby hour and alarm time. The
numbers below have a built in 20% derating factor for the battery amp-hour capacity.
*For FM Installation only
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
AH
Multiply by the Derating Factor
x 1.25
Total ampere hours
required
Table 3-4: Maximum Battery Standby Loads for 24 Hour Standby
Rechargeable
Battery Size
24 hr Standby,
5 mins. Alarm
24 hr Standby,
15 min alarm
24 hr Standby,
20 min alarm
17AH
18AH
24AH
33AH
35AH
40AH
55AH
Table 3-5: Maximum Battery Standby Loads for 90 Hour Standby*
Rechargeable
Battery Size
90 hr Standby,
5 min alarm
90 hr Standby,
15 min alarm
90 hr Standby,
20 min alarm
33 AH
N/A
N/A
N/A
40 AH
347 mA
331 mA
322 mA
55 AH
480 mA
464 mA
456 mA
Warning
Honeywell Silent Knight does not support the use of batteries smaller than those listed in Table 3-4 and Table 3-5. 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 and Table 3-5 to calculate the correct battery amp hour rating
needed for your installation. It is recommended that you replace batteries every five years.
Table 3-3: Current Draw Worksheet for SD SLC Devices
Device
# of Devices
Current per Device
Standby
Current
Alarm
Current
