SC Series User Manual

4-1-1. Battery charging function description

The SC series 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). This causes the battery charger to look like a

resistor to the line (forces the charge current wave shape to mirror the voltage wave shape). 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 translates into 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 for acceptable AC voltage. Once the AC

voltage is accepted, the AC transfer relay closes the charge mode begins. After the charge mode begins,

the inverter’s battery voltage is monitored to determine the charging stage. The charger will skip the Bulk

and Absorb charge 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.

The SC-1200/2000 three stages include an automatic 3-stage charging process: Bulk, Absorb, and Float

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. The AC input voltage falls below 90 VAC @1xx series / 180 VAC

@2xx series– the charger will stop charging to help stabilize the incoming AC voltage. The Charge

mode provides up to three separate charging stages: Bulk Charging, Absorb charging and Float Charge.

Fig. 9

：

Three step charge system