Smith-Root APEX BACKPACK, User Manual

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APEX BACKPACK
www.smith-root.com
EFFECTS OF TEMPERATURE
The temperature at which a battery
is used also affects the relative ca-
pacity of the battery. In cold weather
the shocking time will be less and the
battery will have less capacity (
Figs.
6.3 & 6.4 ).
BATTERY RATING
Batteries are rated at the current
which will reduce the voltage per cell
to 1.67 volts in 20 hours. The heavy-
weight battery has a 12 amp hour
rating. However its life at 100 watt
continuous discharge would be only
120 minutes. As the discharge current
is increased, the efficiency and relative
capacity decreases (
Fig. 6.1 ).
BATTERY LIFE
Each time you cycle a battery it loses
some of its ability to take a charge.
Deep cycle batteries are capable of
being charged and discharged from
100 up to 1,000 times, depending on
the depth of the discharge and the
type of charger used. Service life and
shelf life are both adversely affected
by extreme temperatures.
BATTERY STORAGE
Batteries stored at room temperature
will self- discharge at 3% to 6% per
month. Storage temperature above
20°C (68°F) should be avoided. Shelf
life can be increased by storing in a
climate-controlled environment. Bat-
teries should be fully charged before
storing and should be recharged every
three months.
Life Load Capacity
20 hr 0.60A 12.0Ah
10 hr 1.05A 10.5Ah
5 hr 1.95A 9.7Ah
1 hr 7.20A 7.2Ah
30 min 12.00A 6.0Ah
15 min 20.00A 5.0Ah
Fig. 6.1 Relative capacity of 12Ah deep cycle battery. Fig. 6.2 Discharge curves for
Fig. 6.3 Effect of temperature battery life.
Fig. 6.4 Effect of temperature on capacity.