Battery Charger Functions; Multi-Stage Charging Process - Xantrex XW4024-120 Operation Manual

Battery Charger Functions

Multi-Stage Charging Process

Bulk Stage
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When AC power is available, the XW Inverter/Charger can operate as a battery
charger. Different battery types and chemistries require different charging voltage
levels. Not charging batteries at the required levels can shorten battery life or
possibly damage them. The XW Inverter/Charger is configured at the factory to
work with the battery types recommended for inverter applications. If the default
settings do not work for your specific installation, you can adjust the charge stage
settings (as recommended by the battery manufacturer) on the Custom Battery
Settings menu (see page 3–15). It will be necessary to select the voltage levels
required and to set the voltage limits for the various stages of charging.
Note:
This information is provided for guidance only. Variations in battery chemistry
and site-specific environmental considerations mean that you should consult your system
designer or battery manufacturer for specific recommendations for appropriate battery
voltage and current settings.
The charging cycle uses a multi-stage charging process to maintain the batteries.
Whenever AC power that is within the range of the inverter's settings is present at
the inverter's input, it passes power through to the connected load and begins
charging the batteries.
Bulk Stage
Charging
Started
DC Voltage
Increased Voltage
Max Charge Rate
Setting
Constant Current
DC Current
Time
Figure 3-4 Three-Stage Battery Charging Cycle
Bulk charge is the first stage in the charging process and provides the batteries
with a controlled, constant current. Once the battery voltage rises to the bulk
voltage threshold, the charger switches to the Absorption stage.
Absorption Stage
Bulk/Absorption
Volts Setting
Absorption Time
Constant Voltage
Reduced Current
Reduced Current
Charger Settings Menu
Float Stage
Float Volts Setting
Reduced Voltage
3–11