2.3
Battery charging explained
Most standard selectable Omnicharge Solar charge programs perform a 3-stage IUoUo charging
process comprising of a "Bulk/MPPT" , an "Absorption/Boost", and a "Float" stage. All of course for
as long as there is sufficient sunlight. The image below visualizes the 3-stage charging process:
In the Bulk/MPPT stage the charger delivers full available output current and typically returns
approximately 80% of charge back into the battery, once the charge voltage is reached. During this
stage the charger runs in MPPT mode, transferring maximum PV power into the battery.
When the Charge voltage has been reached, the Absorption/Boost stage will be entered. In this
stage the voltage will be held constant and the current will decline automatically as function of the
battery's state of charge. Typically, this stage will return the final 20% of charge to battery. When the
absorption time-out of 2 hours (= factory default) has been reached the float stage will be entered.
For lithium batteries the charger will remain in the absorption stage as long as there is sufficient
solar power available.
Once every 30 days and only if a Flooded (open lead acid type) battery is selected, the Omnicharge
Solar charger will automatically perform a mild equalization charge, setting the Absorption/Boost
voltage 0.4V @ 12V or 0.8V @ 24V higher than the normal voltage level for a maximum of 2 hours.
This process will help minimize the acid stratification and sulfation that typically occurs in all flooded
batteries. When you do not wish to have this automatic mild equalize charge performed on your
Flooded batteries or wish to alter the equalization voltage level, please create a user defined /
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