Magnum Energy MMS-E Series User Manual

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2.8.1 Neutral to Safety Ground Bonding

The IEC (International Electrotechnical Commission) provides the
standards for safely wiring mobile (caravan, boat, or truck) installa-
tions. These wiring standards require the AC source (inverter, shore
power, or a generator) to have the neutral conductor tied to ground.
These standards also require that the AC neutral be connected to
safety ground (often called a “bond”) in only one place at any time.

If more than one bond is established, currents can circulate between
neutral and ground and cause ground-loop currents. These “ground-
loops” can trip GFCIs and cause an electric shock hazard.

In mobile installations there may be multiple AC sources (i.e., shore
power, generator, or inverter), which means there may be the potential
of having multiple neutral to ground connections.

2.8 AC Wiring

This section describes the required AC wire size and overcurrent pro-
tection for the MMS-E. It also provides information on how to make
the AC connections.

WARNING: All wiring should be done by a qualiﬁ ed per-
son or a licensed electrician following all local/IEC codes.

Connect a short wire (same rating as the DC wires) to one end of the
fuse block and the other end of the short wire to the positive terminal
of the last battery string (see Figure C4). This is essential to ensure
even charging and discharging across the entire battery bank.

Ensure the DC wire connections (to batteries, inverter, and fuse lugs/
DC circuit breaker) are ﬂ ush on the surface of the DC terminals, and
the hardware (lock washer and nut) used to hold these connections
are stacked correctly (see Figures 2-4 and 2-5).

Verify all DC connections are torqued from 13.6 to 16.3 N-m.

Once the DC connections are completely wired and tested, coat the
terminals with an approved anti-oxidizing spray.

Press the red and black terminal covers on to the inverter’s DC con-
nectors to secure them in place.

If batteries are in an enclosure, perform a ﬁ nal check of the hold-down
brackets and all connections. Close and secure the battery enclosure.

2.0 Installation

2.8.2 AC Wiring Connections

For the MMS912E model, the AC input and output wiring is performed
in the AC wiring compartment. This compartment is accessed via the
top panel (see Figure 1-2, Item 8). If the panel cover is installed,
remove the two Phillips screws on the cover to access the AC wiring
compartment and locate the inverter’s AC wiring. There is a label
located in the AC access compartment which gives information on