Dometic SMP439, Installation And Operating Manual

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EN
SMP439, 439-08 Using the device
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1: I phase (bulk)
The empty battery is charged with constant current (100 % charging current). As
soon as the battery voltage has reached the charging voltage the charging current
decreases.
2, 3, 4: U0 phase (absorption)
During the 3-step absorption phase (U0 phase) the voltage remains constant (U0).
Once the battery is completely charged, the U0 phase has finished.
5: U phase (float)
After the U0 phase, the battery charger switches to conservation charging function
(see chapter “Output data” on page 21) (U phase).
Connected DC loads are powered by the device. Only if the power required
exceeds the capacity of the device is this surplus power provided by the battery.
6: 12-day conditioning
Every 12 days and only if battery voltage is below 12.8 V, the battery charger
switches back to phase 1 in order to revive the battery and prevent any fatigue
symptoms such as sulfation. If battery voltage is over 12.8 V, the battery charger
switches back to phases 2 to 4 for 85 minutes and switches then to phase 5.
U0 U
U
I
I
1
100 %
6 %
2 3 4
5
t
U/V
I/A
6