Exide Technologies Section 95.10 User Manual
Page 14
9.6 EFFECTS OF FLOAT VOLTAGE
Float voltage also has a direct effect on the service life of your battery. A float voltage
above the recommended limits reduces service life. The chart below shows the effects
of float voltage (temperature corrected, see section 9.1) on battery life.
For example: A battery has a design life of 10 years, but the actual annual average float
voltage is 2.33 volts per cell. The projected life of the battery is calculated to be 5 years
[10 years - (10 X 0.50) = 5 years].
Voltage records shall be maintained by the user in accordance with the maintenance
schedule published in this manual. To obtain the optimum service life from the battery,
it is important to make sure the battery’s float voltage is within the recommended range.
SECTION 10 - EQUALIZATION
10.0 EQUALIZING CHARGE
Under normal operating conditions an equalizing charge is not required. An equalizing
charge is a special charge given to a battery when non-uniformity in voltage has
developed between units. It is given to restore all units to a fully charged condition.
Use a charging voltage higher than the normal float voltage and for a specified number
of hours, as determined by the voltage used.
The recharge parameters of Section 9.3 apply for this section also.
Non-uniformity of units may result from low float voltage due to improper adjustment of
the charger or a panel voltmeter which reads an incorrect (higher) output voltage. Also,
variations in unit temperatures greater than 3°C (5°F) in the series string at a given
time, due to environmental conditions or battery arrangement, can cause low voltage
batteries.
10.1 EQUALIZING FREQUENCY
An equalize charge should be given when either of the following conditions exist.
A. The float voltage of the pilot unit (or any unit for quarterly readings ) is less than
2.21 VPC.
B. A recharge of the battery is required in a minimum time following an emergency
discharge.
11
Percent
Reduction
In Battery life
0%
50%
75%
Temperature corrected 25°C (77°F)
Float voltage per cell
Minimum
Maximum
2.25
2.30
2.31
2.35
2.36
2.40