Exide Technologies Section 92.30 - Manual (Page 13)

9.3 RECHARGE
All batteries should be recharged as soon as possible following a discharge with constant voltage chargers.
However, to recharge in the shortest period of time, raise the charger output voltage to the highest value
that the connected system will permit. Do not exceed 2.40 VPC. The maximum recommended charge
current for the battery is 35A/100Ah of battery rated capacity.
9.4 DETERMINING STATE OF CHARGE
If the normal connected load is constant (no emergency load connected), the following method can
be used to determine the approximate state of charge of the battery. This state of charge can be
identified to some degree by the amount of charging current going to the battery. When charging, the
current read at the charger ammeter will be a combination of the load current plus the current
necessary to charge the battery. A condition where the current remains constant for a period of three
consecutive hours would reflect approximately 90 to 95% state of charge.
If the normal connected load is variable (e.g., telecommunications), the following method can be
used to check the state of charge of the battery. With the battery on float and stabilized, measure the
voltage across a pilot unit. If the voltage is stable for three consecutive hours, the battery is
considered 100% charged.
9.5 EFFECTS OF TEMPERATURE
Temperature has a direct effect on
the life of a battery. The design life
of the battery is based on an
average annual temperature of
25°C (77°F). As the temperature
increases above 25°C (77°F), the
life of the battery decreases. The
chart below shows the effects of
temperature.
For example: If a battery has a design life of 10 years at 25°C (77°F), but the actual annual average
battery temperature is 35°C (95°F), the projected life of the battery is calculated to be only 5 years
[10 years - (10 years X 0.50) = 5 years].
Temperature records shall be maintained by the user in accordance with the maintenance schedule
published in this manual. The battery temperature shall not be allowed to exceed the maximum
temperature shown above. It is important to maintain the battery temperature as close to 25°C (77°F)
to achieve the optimum service life from your battery.
Maximum Annual
Average Battery
Temperature
25°C (77°F)
30°C (86°F)
35°C (95°F)
40°C (104°F)
45°C (113°F)
50°C (122°F)
Maximum
Battery
Temperature
50°C (122°F)
50°C (122°F)
50°C (122°F)
50°C (122°F)
50°C (122°F)
50°C (122°F)
Percent
Reduction
In Battery Life
0%
30%
50%
66%
75%
83%
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