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5. CHARGING LOGIC
5.1 3-stage Charging
In general, this solar charge controller is designed with 3-stage battery charging
algorithm for fast, efficient, and safe battery charging. The following picture shows the
sequence of charging stages.
1)
Bulk charge stage
In bulk charge stage, charge current begins to flow, typically at the maximum rate of
the charge source. The controller will supply solar power to charge battery as much as
possible.
2)
Absorption stage
When battery charging voltage is reached to Absorption voltage point, the charging
stage changes from bulk charge to Absorption. Constant-voltage regulation is used to
maintain battery voltage at the Absorption stage.
If the charging current drops to one-tenth of the maximum charging current setting
point, the charging status will change to Float stage.
