8
2.3
Lead Acid - Four Stage Charge Curve
Four-Stage Battery Charging Algorithm
:
The LMESpro battery charger is designed with four stage battery
charging algorithms to prevent overheating of the battery and extend the life of the lead acid battery. The four
stages are: Bulk/Absorption/Float/Equalize. This four-stage algorithm allows the battery to be fully charged with
less stress, preventing battery overheating, over gassing and reaching maximum battery life. It can also keep
batteries in a fully charged state (known as
“float”) indefinitely.
Bulk Charge:
In this stage, the battery voltage has not yet reached up to absorption voltage and 100%
of rated current is used to recharge the battery. Charger initiates this mode when the battery voltage is
less than 2.1 Volts per cell for more than 90 seconds. Provides full current until the battery reaches 102%
of its absorption voltage reference.
Absorption:
When the battery has recharged to the Absorption voltage level, constant-voltage regulation
is used to prevent heating and excessive battery gassing. The charger will hold the absorption voltage
mode until the battery is determined to be fully charged. The absorption mode detects the full charge
condition by either the current tapering down to 0.5 Amps, or 4-Hrs has elapsed in the absorption mode.
Float:
After the battery is fully charged, the Charge Controller reduces the charging voltage to the float
mode.
Equalize (NiCad and Flooded battery types only):
The Charge Controller will equalize the battery
for three hours. The Equalize charging mode raises the battery voltage above the standard absorption
voltage. This process prevents electrolyte stratification and equalizes the individual cell voltages within
the battery.
Figure 9
–
Lead Acid Four-Stage Charge Curve
