Xantrex Freedom SW Series, Руководство пользователя, Страница: 93 / 122

97-0019-01-01 79
Battery Charging Reference
Absorption Stage
Absorption charge is the second stage of battery charging and
provides the batteries with a controlled, constant voltage.
During this stage, the current drawn by 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. The timer begins when the battery
voltage is above the bulk termination voltage for three
minutes.
The Freedom SW transitions to the float stage if either one of
the following two conditions are met:
1. The charge current allowed by the batteries falls below
the exit current threshold, which is equal to 2% of the
programmed battery capacity (for a 500 amp-hour battery
bank, this would be 10 amps), for three minutes.
2. The Freedom SW has been in absorption for the
programmed maximum absorption time limit. The default
is 3 hours, but the time limit is programmable from 1
minute to 8 hours.
Table 20
Preset Absorption Voltage Settings
Battery Type
Preset Absorption Voltage
12V models 24V models
Flooded 14.4 28.8
Gel 14.2 28.4
AGM 14.3 28.6
Custom 14.4
(changeable) 28.8
(changeable)
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.
NOTE:
To make sure 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 per cent 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.
FSW Owners Guide.book Page 79 Tuesday, August 7, 2018 9:03 AM