Two-Stage Charging; Float Only Charging - Xantrex XPLORE 120A 12V Owner's Manual

Two-Stage Charging

The two-stage charging mode employs the following sequence:
Bulk and Absorption. It runs similar to the three-stage sequence
except that there is no float stage; after the absorption stage the
charger stops providing current to the battery and the charger
output drops to 9 VZ. In this manner, DC loads draw power
supplied by batteries and the charger enters a "rest or standby
stage."
Like the three-stage sequence, the charger will restart the
charging cycle in the Bulk stage if the lowest battery voltage of the
banks drops below 12.5 V (12 VZ chargers) for 15 minutes. After
21 days, the charger will automatically restart charging in order to
refresh the batteries.
Figure 19 Two-Stage Charging Process
Vbat = Vabs
lout < 10% lrating
for 1 minute
for 1 minute
Battery Voltage
GO TO BULK when
Vbat < 12.5 V for
Charge
15 minutes
start
ABS
BULK
CV
ABS CV timeout
max 5 hrs
REST (Standby)
Start of
timeout max 7 days
charging cycle
975-1038-01-01
9V
REST
(Standby)
Time

Float Only Charging

The float-only charging mode maintains a maximum charging
voltage equal to a preset float voltage. A float stage is applied
steadily to the battery.

Two-Stage Charging

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