3.3 PV configuration
● 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 or 250V, depending on model.
For example:
24V battery, mono- or polycristalline panels, max PV voltage 150V:
● 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, mono- or polycristalline panels, max PV voltage 250V:
● Minimum number of cells in series: 144
(4x 12V panel or 2x 24V panel in series).
● Maximum: 360 cells (10x 12V or 5x 24 panel in series).
Remark: at low temperature the open circuit voltage of a 216 cell solar
array may exceed 150V, and the open cicuit voltage of a 360 cell array
may exceed 250V, depending on local conditions and cell specifications. In
that case the number of cells in series must be reduced.
3.4 Cable connection sequence (see figure 1)
First: connect the battery.
Second: if required, connect the remote on-off and programmable relay
Third: connect the solar array (when connected with reverse polarity, the
controller will heat up but will not charge the battery).
3.5 Remote on-off
The left terminal is connected to the internal 3,3V supply, with a resistor in
series for short circuit protection.
The right terminal (marked as + or marked as H) will switch the controller
on if >3V is applied, and will switch the controller off if <2V is applied or if
the terminal is left free floating.
The recommended use of the remote on-off is:
a. A switch wired between the left and right terminal
b. A switch wired between battery plus and the right terminal.
c) A switch between the right terminal and the charge disconnect terminal of a VE.Bus
BMS
(also see the MPPT Excel sheet on our website)
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