ProStar MPPT Operator’s Manual
41
4.0
When to Equalize?
The ideal frequency of equalizations depends on the
battery type (lead-calcium, lead-antimony, etc.), the depth
of discharging, battery age, temperature, and other factors.
One very broad guide is to equalize flooded batteries every
1 to 3 months or every 5 to 10 deep discharges. Some
batteries, such as the L-16 group, will need more frequent
equalizations.
The difference between the highest cell and lowest cell in a
battery can also indicate the need for an equalization. Either
the specific gravity or the cell voltage can be measured.
The battery manufacturer can recommend the specific
gravity or voltage values for your particular battery.
Preparation for Equalization
First, confirm that all of the system loads are rated for the
equalization voltage. Consider that at 0°C (32°F) the equal-
ization voltage will reach 16.75 volts for L-16 batteries with
a temperature sensor installed. Disconnect any loads at risk
of damage due to the high input voltage.
If Hydrocaps are used, be sure to remove them before start-
ing an equalization. Replace the Hydrocaps with standard
battery cell caps. The Hydrocaps can get very hot during an
equalization. Also, if Hydrocaps are used, the equalization
should be set for manual only (DIP switch #7 is Off).
After the equalization is finished, add distilled water to each
cell to replace gasing losses. Check that the battery plates
are covered.
Equalize a Sealed Battery?
The
Battery Charging Settings
table (see table 4-1 in this
section) shows two sealed battery settings with an Equal-
ization cycles. These are minimal “boost” cycles to level
individual cells. This is not an equalization, and will not vent
gas from sealed batteries that require up to 14.4V charg-
ing (12V battery). Many VRLA batteries, including AGM and
gel, have charging requirements up to 14.4V (12V battery).
Depending on the battery manufacturer’s recommendation,