Connection Of The Ac Cabling - Victron energy MultiPlus-II 48/3000/35 Manual

4.3. Connection of the AC cabling

The MultiPlus-II is a safety class I product (supplied with a ground terminal for safety purposes). Its AC input
and/or output terminals and/or grounding point on the outside of the product must be provided with
an uninterruptible grounding point for safety purposes.
The MultiPlus-II is provided with a ground relay (relay H, see appendix B) that automatically connects the
Neutral output to the chassis if no external AC supply is available. If an external AC supply is provided,
the ground relay H will open before the input safety relay closes. This ensures the correct operation of an
earth leakage circuit breaker that is connected to the output.
• In a fixed installation, an uninterruptable grounding can be secured by means of the grounding wire of the
AC input. Otherwise the casing must be grounded.
• In a mobile installation (for example, with a shore current plug), interrupting the shore connection will
simultaneously disconnect the grounding connection. In that case, the casing must be connected to the
chassis (of the vehicle) or to the hull or grounding plate (of the boat).
In case of a boat, direct connection to the shore ground is not recommended because of potential galvanic
corrosion. The solution to this is using an isolation transformer.
This unit or system is provided with fixed trip limits and shall not be aggregated above 30 kw on a single point
of common connection.
A blade tool of 2.5mm (e.g. a screwdriver) is required to operate the spring loaded AC terminal blocks.
The terminal blocks can be found on the printed circuit board, see Appendix A.
Do not invert neutral and phase when connecting the AC.
The shore or mains cable must be connected to the Multi with the aid of a three-wire 90ºC (194ºF) copper cable.
Rated current
Recommend fuse or circuit breaker
Minimum wire gauge
Ferrule pin length / stripping length
The inverter does incorporate a mains frequency isolating transformer. This precludes the possibility of DC current at any AC port.
Therefore type A RCD's can be used.
• AC-in
The AC input cable can be connected to the terminal block 'AC–in'.
From left to right: "N" (neutral), "L2" (phase 2), "PE" (earth) and "L1" (phase 1)
The AC input must be protected by a fuse or magnetic circuit breaker rated at 50A or less, and cable cross-section
must be sized accordingly. If the input AC supply is rated at a lower value, the fuse or magnetic circuit breaker should be
down sized accordingly.
• AC-out-1
The AC output cable can be connected directly to the terminal block 'AC-out'.
From left to right: "N" (neutral), "PE" (earth) and "L" (phase)
With its PowerAssist feature the Multi can add up to 3kVA (that is 3000 / 120 = 25A) to the output L1 during periods of peak
power requirement. Together with a maximum input current of 50A this means that the output can supply up to 50 + 25 = 75 A.
An earth leakage circuit breaker and a fuse or circuit breaker rated to support the expected load must be included in series with
the output, and cable cross-section must be sized accordingly. Victron Energy recommends to use the Blue Sea systems GFCI
circuit breakersPN. 309X or 310X. The maximum rating of the fuse or circuit breaker is 75A.
• AC-out-2
A second output is available that disconnects its load in the event of battery operation. On these terminals, equipment is
connected that may only operate if AC voltage is available on AC-in-1, e.g. an electric boiler or an air conditioner. The load on
AC-out-2 is disconnected immediately when the MultiPlus-II switches to battery operation. After AC power becomes available
on AC-in-1, the load on AC-out-2 will be reconnected with a delay of approximately 2 minutes. This to allow a genset to
stabilise.
Page 13
MultiPlus-II 48V 3kVA 120V
AC-in AC-Out-1
50 A 75 A
50 A 75 A
AWG 6 AWG 6
0.7 inch (18 mm) 0.7 inch (18 mm)
AC-Out-2
32 A
32 A
AWG 10
0.7 inch (18 mm)
Installation