Victron energy BlueSolar MPPT 150/45-Tr Anleitung Seite 7

3.2 PV configuration (also see the MPPT Excel sheet on our
website)
● The controllers will operate only if the PV voltage exceeds
battery voltage (Vbat).
● PV voltage must exceed Vbat + 5V for the controller to start.
Thereafter minimum PV voltage is Vbat + 1V.
● Maximum open circuit PV voltage: 150V.
The controllers can be used with any PV configuration that
satisfies the three above mentioned conditions.
For example:
24V battery and mono- or polycristalline panels
● Minimum number of cells in series: 72 (2x 12V panel in series
or one 24V panel).
● Recommended number of cells for highest controller
efficiency: 144 cells (4x 12V panel or 2x 24V panel in series).
● Maximum: 216 cells (6x 12V or 3x 24V panel in series).
48V battery and mono- or polycristalline panels
● Minimum number of cells in series: 144
(4x 12V panel or 2x 24V panel in series).
● Maximum: 216 cells.
Remark: at low temperature the open circuit voltage of a 216
cell solar array may exceed 150V, depending on local conditions
and cell specifications. In that case the number of cells in series
must be reduced.
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.
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