Specifications

lMl66-107 Maintenance
Question
How long will battery back-up last?
Answer
Anyone can calculate the actual
minimum battery back-up time for any
configured system by using the
following formula:
System Manual Reference
T= (K) (e)
1 + W.1) W)l
T = Back-up time in hours
K = Constant:
0.9 for 408 system with or without a
408 expansion module
0.8 for 816 system with or without
one or two 408 expansion modules
.8 for 1632 system with or without
one or two 408 expansion modules
e = Ampere-hour capacity of battery
(for example = BBL02 = 15)
N = Total number of stations
Example: Assume that a 1632 system,
two 408 expansion modules, and 48
stations are installed, along with a
BBU02 battery assembly to provide
backup power.
T= (0.8) (15) -
= 12 = 2.1 hrs.
1 + [(O.l) (48)] 5.8