Technical Notes - Outback Power Systems FLEXnet DC User Manual

Technical Notes

Battery Charge Factor (BCF)
Some energy is lost both when recharging and discharging a battery. The FLEXnet DC
compensates for these losses by discounting the amp-hours charging the battery, meaning
it doesn't count every hour used for recharging as actually recharging. Some of them are lost
due to heat and gassing. The FLEXnet DC's default BCF is 94, which means for every 100 amp
hours of charge to the battery, only 94 are shown in the amp hour display for a BCF of 94%.
This means 6% of the amp hours is lost.
As the system goes through a few recharging cycles, the range of state-of-charge (SOC)
percentages will vary, but should fall into a predictable range. This allows the user to change
the BCF if necessary for more effi cient recharging. If the SOC displays as full before the battery
charge settings are met (either before the time setting or amp hour setting is satisfi ed), the
BCF should be lowered because it's assuming too many amp hours have been recharging the
battery. By lowering the BCF, the FLEXnet DC will read more hours as being unused due to
ineffi ciency.
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