Dometic Buttner POWER & CONTROL MT ICC Montage- Und Bedienungsanleitung Seite 19

Battery charging function
The selectable charging programs (see chapter "Setting the charging program" on page 23) perform a
charging process in four phases, referred to as IU0U characteristics.
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1: Constant current phase (Bulk)
The battery is constantly charged with the maxi-
mum charging current (100 %). The charging cur-
rent decreases when the battery has reached a
state of charge of 75 % (90 % for LiFePO4 batter-
ies). The duration of the constant current phase
depends on the condition of the battery, the load
from the DC loads and the state of charge.
2: Constant voltage phase (Absorption)
The constant voltage phase starts when the
absorption voltage (U1) is reached. The charging
current is reduced depending on the state of
charge. During the constant voltage phase, the
battery voltage is kept constant at a high level and
the state of charge is increased to 100 %. The dura-
tion of the constant voltage phase depends on the
battery type, but is terminated after a maximum of
4 h (absorption time-out).
3: Trickle charging phase (Float)
The trickle charging phase starts when the
charging current falls below a minimum value or
the absorption time-out has been reached.The
trickle charging phase serves to maintain the state
of charge (100 %) and runs at lowered charging
voltage (U2) and variable current. If DC loads are
connected, they are powered by the device.
EN
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If the power required exceeds the capacity of the
device, this surplus power is provided by the bat-
tery and the battery voltage drops. As soon as the
battery voltage has dropped to a certain value the
device re-enters the constant current phase and
charges the battery.
4: Reconditioning phase (Pulse)
Once a week, the device switches back to the con-
stant voltage phase for a short time (max. 1 h) in
order to revive the battery. This prevents any
fatigue phenomena such as sulfation or electrolyte
stratification.
Temperature sensor
With the temperature sensor connected the
inverter charger combination adapts the charging
voltage (for lead batteries) or the charging current
(for LiFePO4 batteries) according to the measured
temperature at the battery.
I
NOTE
• Charging voltage adaptation:
30 mV/°C (referenced to 20 °C)
• Charging current adaption:
Charging current reduction up to 10 %
of the maximum charging current (at
battery temperatures <0 °C) or to 0 %
(at battery temperatures >52 °C)
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