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EN
3.3 Cable connection sequence (see figure 1)
First:
connect the battery.
Second:
connect the solar array (when connected with reverse polarity,
the controller will heat up but will not charge the battery).
3.4 More about automatic battery voltage recognition
The system voltage is stored in non volatile memory.
In case of a 24V or 48V battery, a reset (to 12V) occurs only when the
output voltage decreases to less than 2V and the voltage on the PV input
exceeds 7V. This may occur when the battery has been disconnected
before PV voltage starts to rise in the early morning. When the (24V or
48V) battery is reconnected later during the day, the system voltage is
restored to 24V resp. 48V after 10 seconds if the battery voltage exceeds
17,5V resp. 35V.
Automatic voltage recognition can be switched off and a fixed 12/24/36 or
48V system voltage can be set with a computer, a smartphone or a
pluggable LCD display.
The controller can be reset by short circuiting the output and applying a
voltage exceeding 7V on the input (for example with a small power supply,
or a solar panel) during a few seconds. After a reset, the controller will
automatically adjust itself to a 12V system, a 24V system (when
connecting a 24V battery with at least 17,5V) or a 48V system (when
connecting a 48V battery with at least 35V). A computer, a smart phone or
a pluggable LCD display is required to set the MPPT to 36V.
3.5 Battery charging information
The charge controller starts a new charge cycle every morning, when the
sun starts shining.
The maximum duration of the absorption period is determined by the
battery voltage measured just before the solar charger starts up in the
morning:
Battery voltage Vb (@start-up)
Maximum absorption time
Vb < 23,8V
6h
23,8V < Vb < 24,4V
4h
24,4V < Vb < 25,2V
2h
Vb > 25,2V
1h
(divide voltages by 2 for a 12V system and multiply by two in case of a 48V
system)
If the absorption period is interrupted due to a cloud or due to a power
hungry load, the absorption process will resume when absorption voltage is
reached again later on the day, until the absorption period has been
completed.
