Xantrex Technology 2500 - Manual (Page 19)

90-0115-00
10/97 Fltman.pm65
charging cycle. The battery voltage will
increase to 16.3 using the cool temperature
wet cell setting. This will cause the battery
bank to gas profusely and will accomplish
the following:
1. Removal of residual sulfate. Each time
a battery is cycled (discharged and re-
charged), a small amount of sulfate is left on
the plates. Over time, this gradual build-up
of sulfate will compromise the performance
of the battery. By applying an equalizing
charge, the sulfate is returned back to the
electrolyte, raising the specific gravity and
fully exposing the active material of the
plates.
2. Bring all cells to the same potential.
All lead-acid batteries are made up of indi-
vidual 2 Volt cells. As the battery bank is
cycled, slight differences in the cells result
in different cell voltages, affecting the over-
all charge effectiveness. Equalizing brings
all cells up to the same voltage and the
electrolyte in each cell to the same specific
gravity.
3. Mixing up of the electrolyte. Electro-
lyte in battery cells tend to separate into
layers of acid and water. The vigorous
boiling action of the battery during equaliz-
ing serves to physically mix the electrolyte.
BATTERY CHARGING
Equalizing is not required on gel cell
batteries. You will note that if the dip
switches are set in one of the two gel cell
positions, the equalizing charge voltage is
the same as the bulk charge voltage, there-
fore, equalizing is equivalent to an 8-hour
acceptance stage and is not harmful.
To limit the DC current during equaliz-
ing to less than 15 Amps, turn on dip
switches 7 and 8 before starting the equal-
ize charge. Do not operate AC loads that
are on the output of the inverter/charger
when equalizing.
Charging Over-Discharged Batteries
Charging into a battery bank with a
terminal voltage of less than 8 Volts pre-
sents a special problem for the unit. If this
situation arises, the unit will attempt to
charge for 1 minute. If the inverter senses
excessive ripple voltage, it will shut down to
protect itself.
To successfully charge an over-
discharged battery, you must remove as
much DC load as possible. Set dip
switches 7 and 8 to the ON position to limit
the amount of charge current and the result-
ing ripple voltage. After the battery voltage
has reached 10 Volts, these switches can
be set to their previous positions.
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