Dometic BUTTNER MT150PP Instructions De Montage Et De Service page 18

Technical description
6.3 Battery charging function
The charging characteristics for fully automated continuous operation without monitoring are referred to as IU0U
characteristics (see charging curve in fig. 2, page 4).
1: I phase (Constant current phase)
At the beginning of the charging process, the empty battery is constantly charged with the maximum charging cur-
rent (100 %). The charging current decreases when the battery has reached a state of charge of 75 % (90 % for lith-
ium batteries). Batteries with a voltage of 0 V are charged with reduced charging current until the battery voltage
exceeds 9 V.The duration of the I phase depends on the state of the battery, the load from the consumers and the
state of charge. For safety reasons the I phase is terminated after a maximum of 15 h (in case of battery cell defects
or similar).
2: U1 phase (Constant voltage phase)
The U1 phase starts when the battery is fully loaded. The charging current is reduced. During the U1 phase, the bat-
tery voltage is kept constant at a high level. The duration of the U1 phase depends on the battery type and the
depth of discharge.
3: U2 phase (Trickle charging)
The U2 phase serves to maintain the battery capacity (100 %).The U2 phase runs at lowered charging voltage and
variable current. If DC loads are connected, they are powered by the device. Only if the power required exceeds
the capacity of the device, this surplus power is provided by the battery. The battery then is discharged until the
device re-enters the I phase and charges the battery.The U2 phase is limited to between 24 and 48 h depending
on the battery type.
6.4 Temperature sensor
With the temperature sensor connected, the solar charge controller adjusts the charging voltage (for lead batter-
ies) or the charging current (for lithium batteries) according to the measured temperature at the battery.
I
NOTE
Without the temperature sensor connected or if the temperature sensor is defective,
the charging voltage is referenced to 20 °C.
The charging characteristics are adjusted as follows:
• For lead acid batteries see fig. 3, page 4
• For lead gel batteries see fig. 4, page 4
• For AGM batteries see fig. 5, page 5
• For LiFePO4 batteries (14.2 V) see fig. 6, page 5
• For LiFePO4 batteries (14.4 V) see fig. 7, page 5
• For LiFePO4 batteries (14.6 V) see fig. 8, page 6
• For LiFePO4 batteries (14.7 V) see fig. 9, page 6
Legend
Charging curve without temperature sensor connected
Charging curve with temperature sensor connected
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MT150PP, MT230PP, MT350PP, MT550PP
EN