Victron energy BlueSolar MPPT 150/35 Manual page 7

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 150 V, 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 24 V or 48 Vbattery, a reset (to 12 V) occurs only
when the output voltage decreases to less than 2 V and the
voltage on the PV input exceeds 7 V. This may occur when the
battery has been disconnected before PV voltage starts to rise
in the early morning. When the (24 V or 48 V) battery is
reconnected later during the day, the system voltage is restored
to 24 V resp. 48 V after 10 seconds if the battery voltage
exceeds 17,5 V resp. 35 V.
Automatic voltage recognition can be switched off and a fixed
12/24/36 or 48 V system voltage can be set with a computer or
a Color Control panel.
Alternatively, the controller can be reset by short circuiting the
output and applying a voltage exceeding 7 V 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
24 V battery with at least 17,5 V) or a 48V system (when
connecting a 48 V battery with at least 35 V).
A computer or a Color Control panel is required to set the MPPT
to 36V.
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