SL2000-112 Manual

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4-1-1. Battery Charging Function Description
SL series is equipped with a PFC (Power Factor Corrected) and PI (Proportional-Integral) multistage battery
charger. The PFC feature controls the amount of power used to charge the batteries to obtain a power factor as
close as possible to 1 (or unity).. The PI feature allows the charger voltage and current to change independently.
These two features maximize the real power available from the AC power source (i.e., utility or generator),
which leads to less power wasted and greater charging capabilities than most chargers today. When an AC
source is connected to the AC input, the inverter begins monitoring AC voltage. Once the AC voltage is
accepted, charge mode begins. After the charge mode begins, the inverter’s battery voltage is monitored to
determine the charging stage. If the battery voltage is low (≤12.8 VDC/12-volt), the charger begins Bulk
charging. If the DC voltage is high (>12.8 VDC/12-volt), the charger will skip Bulk and Absorb stages and go
directly to Final charging. However, if the incoming AC power is lost and returns within 2 minutes the charge
mode returns to the charge stage it was in prior to losing AC input—regardless of the battery voltage.
There are 4 charging stages in SL series, including an automatic 3-stage charging process (see Fig. 1): Bulk,
Absorb, and Final Charge; and a manual Equalization (EQ) charge stage. The automatic 3-stage charge
process provides complete recharging and monitoring of the batteries without damage due to overcharging.
The EQ stage (requires a remote display to enable) is used to stir up stratified electrolyte and to reverse any
battery plate sulfation that may have occurred.If the AC input voltage falls below 90 VAC – the charger will stop
charging to help stabilize the incoming AC voltage.
4-1-2. Bulk Charging
While bulk charging, the charger supplies the battery with controlled constant current. The charger will remain
in bulk charge until the absorption charge voltage (determined by the Battery Type selection) is achieved.
4-1-3. Absorption Charging
This is the second charging stage and begins after the absorb voltage has been reached. Absorb charging
provides the batteries with a constant voltage and reduces the DC charging current in order to maintain the
absorb voltage setting.
4-1-4. Final Charging
The third charging stage starts at the end of the absorb charging . While final charging, the charge voltage is
reduced to the final charge voltage (determined by the Battery Type selection*). In this stage, the batteries are
kept fully charged and ready if needed by the inverter. The Float Charging stage reduces battery gassing,
minimizes watering requirements (for flooded batteries), and ensures the batteries are maintained at optimum
capacity.
Fig. 10 ： Three step charge system