Xantrex XW4024-120, Руководство по эксплуатации

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Configuration
3–12 975-0240-01-01
Absorption Stage Absorption charge is the second stage of battery charging and provides the
batteries a controlled, constant voltage. During this stage, the current supplied to
the batteries slowly decreases. When this current falls below 2% of the battery
capacity, or when the configurable Absorb Time expires, the charger switches to
the Float or NoFloat stage, depending on the selected charge cycle.
Float Stage Float charge maintains a trickle charge on the batteries whenever AC is present on
the inverter’s input. Float charging reduces battery gassing, minimizes watering
requirements (for flooded batteries), and ensures the batteries are in a constant
state of readiness. When three-stage charging is selected, the charger will
automatically switch to the float stage after the batteries have received a bulk and
absorption charge (see Figure 3-4 on page 3–11). The batteries will be maintained
at the default float voltage level for the selected battery type or the voltage
selected under Float Voltage on the Custom Battery Settings menu.
2-Stage 2-Stage (or No Float) mode differs from an ordinary three-stage charge mode in
that it does not continuously maintain the battery at float voltage. Instead, the XW
Inverter/Charger begins charging the battery in bulk mode whenever the battery
voltage drops below the recharge level. While the battery voltage is above the
recharge level the inverter’s AC transfer switch continues to pass power through
from the utility grid to the loads, but does not actively charge the batteries. 2-
Stage mode increases efficiency of utility connected systems by reducing the
amount of power consumed by the inverter and batteries compared to when the
battery is continuously maintained at Float voltage. This feature can extend the
life of most batteries.
To allow Grid Support and Sell Mode to function after battery charging has
completed, it is recommended to set the Charge Cycle to 2-Stage.
Note:
If there are DC loads on the batteries, the charger’s current may never decrease
to a level to initiate the next stage of charging. In this case, the charger would stay in
absorption until the Absorb Time setting is reached.
To ensure the charger does not remain in absorption for too long, adjust Absorb Time on
the Charger Settings menu. The timer begins at the start of the absorption stage and
terminates absorption charging if the charge current does not decrease to below 2% of
the battery capacity before the Absorb Time
setting expires. The Absorb Time setting
may be increased if the charge cycle continually runs the full Absorb Time in the
absence of DC loads. This is an indication of too large a battery bank for the selected
Absorb Time setting.
Note:
The battery voltage can increase above the float voltage when using an external
charging device such as PV arrays, wind turbines, and micro-hydro generators. Be sure
to include appropriate charge management equipment with all external DC sources.
Note:
If the AC input fails or drops below the lower Vac limit (as set in “AC Settings”),
the complete multi-stage charge cycle (Bulk, Absorption, Float/No Float) restarts once
the source AC returns to an in-tolerance condition. If the batteries are already nearly full,
the charge cycle will take little time to complete.