Rockwell Automation 1748 DataSite Configured Panel Installation Instructions - Manual (Page 45)

45 Publication 1748-IN001B-EN-P - May 2009
Appendix
A
DataSite Configured Panel Battery
This appendix provides the following information:
• Environmental Effects on Charge Capacity
• Battery Life Expectancy
Environmental Effects on
Charge Capacity Battery capacity is a function of ambient temperature and the rate of discharge.
The batteries supplied for the DataSite configured panels are rated at a 100%
capacity at 20 °C (68 °F). As shown in the installation section, the increase in
ambient temperature will increase the available capacity of the battery.
Conversely, as the ambient temperature increases, the battery life (usually
measured in months) decreases. The effects of ambient temperature should be
considered when sizing the batteries.
For the DataSite configured panel application, measures have been taken to
reduce the power consumption and the rate of discharge of the batteries.
Additional loads such as lights, displays or measuring equipment on the
DataSite configured panel may cause the capacity of the batteries to decrease
depending on the size of the loads involved.
This figure shows the effect of temperature and rate of discharge on the
charge capacity of the batteries.
Temperature Effects on Battery Capacity and Expected Life
0
10
20
30
40
50
60
70
-40 -35 -30 -25 -20 -15 -10 -5 0 5 10 15 20 25 30 35 40 45 50 55 60 65 70
Temperature (°C)
B
a
tt
er
y L
if
e
E
x
p
e
ct
an
cy (
M
o
n
th
s)
30
40
50
60
70
80
90
100
-40 -31 -22 -13 -4 5 14 23 32 41 50 59 68 77 86 95 104 113 122 131 140 149 158
Temperature (°F)
M
a
x
im
u
m
Ba
tte
ry
Ca
p
a
c
ity
(%
o
f Ra
te
d
Ah
)
Life Expectancy
Optimal operating range
Battery Capacity