SilentKnight EVS - Manual (Page 46)

EVS Series Emergency Voice System Installation Manual
4-24 LS10062-001-SK-E
4.5.9 Calculating Current Draw and Standby Battery
This section helps you determine the current draw and standby battery needs for your
installation (18 Ampere Hours max. will fit in cabinet). Complete the remaining
instructions in Table 4-2.
Batteries larger than 18 AH will not fit in the main control cabinet, and must be
housed in the RBB Accessory Battery Cabinet. Maximum of 33 Amp Hours per
system.
Table 4-2: Current Draw Calculations
Device
No. of
Devices
Current Per Device
Standby
Current
Alarm
Current
EVS-50W 25V 1
Standby: 85 mA 85 mA
Alarm: 525 mA 525 mA
EVS-50W 70.7V 1
Standby: 100 mA 100 mA
Alarm: 580 mA 580 mA
EVS-CE4 0 or 1
Standby: 20 mA 20mA
Alarm (All Channels): 180 mA 180 mA
A Current Subtotals: mA mA
Notification Devices Refer to device manual for number of devices and current ratings.
B Current Subtotals: mA mA
C Total current rating of all devices in system (Line B) X 0.001 A A
D Number of standby hours (24 or 60 for NFPA 72) H
E Multiply line C (standby current) and D:Total standby AH AH
F Alarm sounding period in hours (For example, 5 minutes = 0.0833 hours): H
G Multiply line C (alarm current) and F:Total alarm AH AH
H Add lines E and G (AH = Ampere Hours):Total AH required AH