AIR 40, AIR Breeze, AIR 30, AIR X MARINE and AIR SILENT-X are trademarks of Primus Wind Power 2013 Primus Wind Power Inc.
AIR Owner’s Manual
3-CMLT-2020-A
9
SIMPLE TIPS FOR DEEP CYCLE BATTERY BANK SIZINING
In preparation for battery sizing, know:
ELECTRICAL USAGE -
the amount of energy consumed 1 day in Watt-
hours (Wh)
DAYS OF AUTONOMY
-
days of battery back-up required if unable to
charge the batteries by any means.
DEPTH OF DISCHARGE
-
limit of energy withdrawal to which you will
subject the deep cycle battery bank.
•
Deeper discharge = Shortened battery life.
•
Recommended: never discharge a deep cycle battery below 50% of
its capacity
•
Off-grid applications, a 25% DoD will extend battery life significantly
TEMPERATURE
-
Standard for most battery rating is 25 ° C /(77 °F).
•
Cold temperatures = reduced battery capacity
•
High temperatures = shortened
battery life
RECOMMENDATION
-
Keep the number of parallel strings of batteries to
three or fewer (one is preferred and considered best practice). More than
three strings of batteries, risks shortening battery life due to uneven
charging.
Batteries in Series = Voltage is Additive
Batteries in Parallel = Ah is Additive
*Example: 2 12V 100Ah Battery Bank
Series
24V
100 Ah
Parallel 12V
200 Ah
• A system load of 6,000 Watt-hours per day
•
3 Days of Autonomy (back-up) needed
•
Planned Depth of Discharge (DoD): 40%
•
Battery bank ambient average low 15.6 °C (60 ° F)
CALCULATIONS: calculate battery bank size, use example below:
STEPS:
EXAMPLE:
3 days of Autonomy:
6,000 x 3 = 18,000 Wh
