Installation - Victron energy BlueSolar MPPT 70/15 Manual

3. Installation

3.1. General
● Mount vertically on a non-flammable substrate, with the power terminals facing
downwards.
Mount close to the battery, but never directly above the battery (in order to prevent
damage due to gassing of the battery).
Use cables with 6 mm² cross section. Do not exceed 5 m cable length.
(if the cables to the PV panels must be longer than 5 m, increase cross section or use
parallel cables and install a junction box next to the controller and connect with a short 6
mm² cable to the controller).
20A battery fuse: replacable fuse in the controller, next to the battery terminals.
Grounding: if grounding is required, use one grounding point only. Never ground both
the minus of the solar array and the minus of the battery.
3.2. PV configuration
● The controller 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: 75V.
The controller can be used with any PV configuration that satisfies the three above
mentioned conditions.
For example:
12V battery and mono- or polycristalline panels
● Minimum number of cells in series: 36 (12V panel).
● Recommended number of cells for highest controller efficiency: 72
(2x 12V panel in series or 1x 24V panel).
● Maximum: 108 cells (3x 12V panel in series).
24V battery and mono- or polycristalline panels
● Minimum number of cells in series: 72
(2x 12V panel in series or 1x 24V panel).
● Maximum: 108 cells (3x 12V panel in series).
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