User manual

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FIGURE 6:
Temperature
Sensor
FLOODED BATTERY CAPACITY & TEMPERATURE
Ideal operating temperature for Flooded deep cycle lead-acid batteries is 25°C (77°F).
Battery capacity and cycle life is affected by operating temperature. Operating at higher
temperatures will reduce cycle life due to cell degradation. A cycle life reduction of ~50%
for every 10°C over 25°C (77°F) is expected. Loss of cycle life is not recoverable.
Ex. Continuous operation at 35°C (95°F) will typically reduce battery cycle life by 50%.
Cooler operating temperatures will prolong cycle life. However, low temperatures will
reduce available battery capacity. Capacity is regained as operating temperatures rise.
Operating temperature is considered when sizing a battery bank to meet a required
available Amp-Hour (AH) capacity. As continuous operating temperature drops, the required
rated AH capacity of the battery bank will increase to meet the equivalent capacity. To
calculate the adjusted capacity, use the multiplier in the table below.
TABLE 3: Cold Temperature Capacity Multiplier
EXAMPLE: Calculated loads require 500 AH usable capacity. With an operating temperature
o
f 25°C (77°F), a battery bank with 1000 AH rated capacity is needed. (max 50% DOD)
1000 AH capacity battery bank with a continuous operating temperature of -10˚C (14˚F)
1000 AH x 1.65 = 1650 AH adjusted capacity
Note: as operating temperatures may vary considerably over a 12-month period, the average
temperature and corresponding multiplier may be used to calculate an adjusted capacity.
Cycling frequency, seasonal changes in loads & desired depth of discharge (DOD) should also
be considered when sizing a battery bank to meet a required Amp-Hour capacity.
ºC ºF MULTIPLIER
25º 77º 1.00
20º 68º 1.02
15º 59º 1.06
10º 50º 1.13
5º 41º 1.21
0º 32º 1.35
-5º 23º 1.49
-10º 14º 1.65
-15º 5º 1.95
-20º -4º 2.21
-25º -11º 2.25
OPERATING TEMPERATURE
25ºC 0ºC -15ºC
PERCENTAGE OF AVAILABLE CAPACITY
100% 75% 50%
OPERATING TEMPERATURE
25ºC 30ºC 35ºC
EXPECTED LOSS OF CYCLE LIFE
0% 25% 50%