Victron energy MPPT 150/45-Tr Manuel page 9

3.2 Grounding
● Battery grounding: the charger can be installed in a positive or
negative grounded system.
Note: apply a single ground connection to prevent
malfunctioning of the system.
● Chassis grounding: A separate earth path for the chassis
ground is permitted because it is isolated from the positive and
negative terminal.
● The USA National Electrical Code (NEC) requires the use of
an external ground fault protection device (GFPD). The
Victron MPPT chargers do not have internal ground fault
protection. The system electrical negative should be bonded
through a GFPD to earth ground at one (and only one)
location.
● The charger must not be connected with grounded PV arrays.
WARNING: WHEN A GROUND FAULT IS INDICATED,
BATTERY TERMINALS AND CONNECTED CIRCUITS MAY
BE UNGROUNDED AND HAZARDOUS.
3.3 PV configuration (also see the MPPT Excel sheet on our
website)
● Provide a means to disconnect all current-carrying
conductors of a photovoltaic power source from all other
conductors in a building or other structure. A switch, circuit
breaker, or other device, either ac or dc, shall not be installed
in a grounded conductor if operation of that switch, circuit
breaker, or other device leaves the marked, grounded
conductor in an ungrounded and energized state.
● 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.
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).
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