© 2015 Sensata Technologies
Appendix B – Battery Information
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Appendix B – Battery Information
B-1 Battery Bank Sizing
The size of the battery bank determines how long the inverter can
power the AC loads without recharging. The larger the battery bank,
the longer the run time. Size your battery bank to the system’s
AC load requirements and the length of time required to run the
load from the batteries. In general, the battery bank should not be
discharged more than 50%.
B-2 Battery
Types
Batteries are available in different sizes, amp-hour ratings, voltage,
and chemistries; they also come in liquid or gel, vented or non-
vented, etc. They are also available for starting applications (such
as an automobile starting battery) and deep discharge applications.
Only the deep cycle types are recommended for inverter applications.
Choose the batteries best suited for the inverter installation and
cost. Use only the same battery type for all batteries in the bank.
For best performance, all batteries should be from the same lot and
date. This information is usually printed on a label located on the
battery.
B-3 Battery
Confi guration
The battery bank must be wired to match the inverter’s DC
input voltage speci
fi
cations (12 VDC). In addition, the batteries
can be wired to provide additional run time. The various wiring
con
fi
gurations are:
Series Wiring
Wiring batteries in a series increases the total battery bank output
voltage. A series connection combines each battery in a string until
the voltage matches the inverter’s DC requirement. Even though
there are multiple batteries, the capacity remains the same. In
the example below (Figure B-1), two 6 VDC/200 AH batteries are
combined into a single string—resulting in a 12 VDC/200 AH bank.
6 volts
(200 AH)
6 volts
(200 AH)
overcurrent protection
12-volt battery bank (total capacity = 200 AH)
To
12 VDC
Inverter
Figure B-1, Series Battery Wiring