Appendix G: Calculating The Battery Power Requirements - Siemens SPC4000 Installation & Configuration Manual

Appendix
16.6

Appendix G: Calculating the Battery Power Requirements

116
Siemens Building Technologies
Fire Safety & Security Products
It is important that adequate stand-by power is available to supply all devices in the
event of a Mains supply failure. To ensure that enough power is available, always
connect the appropriate back-up battery and PSU.
The table below gives an approximation of the maximum load current that can be
drawn from each type of battery over the given stand-by periods of 12 hours, 30
hours and 60 hours.
The approximations below assume that the SPC Controller PCB is drawing its
maximum load (no auxiliary load connected, no external bells connected, no
diallers plugged) and that the usable output power from the battery is 85% of its
maximum capacity.
0.85 x Max Battery Capacity (AH)
Standby Time (Hours)
Device with PSU
Max. controller current
Battery
Standby 12 hours
Time
30 hours
60 hours
Tab. 30 Battery Standby Time
See Appendix F for maximum load of devices and modules.
Values listed as N / A indicate that the selected battery does not have the capacity
to power the minimum load of just the SPC Controller for the given standby time.
NOTE
Only Sealed Cell Valve Regulated Battery Types to be used.
For EN compliance the supplied current needs to be supported by the battery for required stand by
time.
- SPC Controller Current
SPC5000
SPC6000
Approx. 200 mA
7 AH 17 AH
296 mA 1004 mA
n.a 282 mA
n.a. n.a.
= Max available load current
SPC4000
SPCP332/333
Approx. 100 mA
7 AH 17 AH
396 mA 1104 mA
98 mA 382 mA
n.a. 141 mA
09.2008