4.3 Connection of the AC cabling
The MultiPlus is a safety class I product (supplied w ith a ground terminal for
safety purposes). Its AC input and/or output terminals and/or
grounding point on the outside of the product m ust be provided w ith
an uninterruptible grounding point for safety purposes.
The MultiPlus is provided w ith a ground relay (relay H, see appendix B) that
autom atically 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 w ill 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 w ire of the AC input. Otherw ise the casing must be
grounded.
- In a mobile installation (for example, w ith a shore current plug),
interrupting the shore connection w ill 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.
The terminal blocks can be found on the printed circuit board, see Appendix A. The shore or mains cable must be connected to the
MultiPlus w ith the aid of a three-w ire cable.
- AC-in
The AC input cable can be connected to the terminal block "AC–in".
From left to right: "PE" (earth), "N" (neutral) and "L" (phase).
The AC input m ust be protected by a fuse or magnetic circuit breaker rated at 100A or less, and cable cross-section must be
sized accordingly. If the input AC supply is rated at a low er value, the fuse or magnetic circuit breaker should be dow n sized
accordingly.
- AC-out-1 (see appendix A)
The AC output cable can be connected directly to the terminal block "AC-out".
With its Pow erAssist feature the MultiPlus can add up to 5kVA (that is 5000 / 230 = 22A) to the output during periods of peak pow er
requirement. Together w ith a maximum input current of 100A this means that the output can supply up to 100 + 22 = 122A.
An earth leakage circuit breaker and a fuse or circuit breaker rated to support the expected load must be included in series
w ith the output, and cable cross-section must be sized accordingly. The maximum rating of the fuse or circuit breaker is 122A.
- AC-out-2 (see appendix A)
A second output is available that disconnects its load in the event of battery operation. On these terminals, equipment is connected that
m ay only operate if AC voltage is available on AC-in, e.g. an electric boiler or an air conditioner. The load on AC-out-2 is
disconnected immediately w hen the MultiPlus sw itches to battery operation. After AC power becomes available on AC-in, the load on
AC-out-2 w ill be reconnected w ith a delay of approximately 2 minutes. This to allow a genset to stabilise.
AC-out-2 can support loads of up to 50A. An earth leakage circuit breaker and fuse rated at max. 50A must be connected in series w ith
AC-out-2.
Note: Loads connected to AC-out-2 w ill be taken into account in the Pow erControl / Pow erAssist current limit setting. Loads directly
connected to the AC supply w ill not be included in the Pow erControl / Pow erAssist current limit setting.
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