6820 / 6820EVS Manual P/N LS10144-001SK-E:C 09/28/2017 27
5. Total does not include isolator devices or accessory bases.
3.7.4 Maximum Battery Standby Load
Tables 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
Rechargeable
Battery Size
24 hr Standby,
5 mins. Alarm
24 hr Standby,
15 min alarm
24 hr Standby,
20 min alarm
17AH 535 mA 473 mA 442 mA
18AH 569 mA 506 mA 475 mA
24AH 769 mA 706 mA 675 mA
33AH 1.07A 1.01A 975 mA
35AH 1.14A 1.07A 1.04A
40AH 1.30A 1.24A 1.21A
55AH 1.80A 1.74A 1.71A
Table 3.4 Maximum Battery Standby Loads for 24 hours 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
Table 3.5 Maximum Battery Standby Loads for 90 hour Standby*
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