Magnum Energy MMS-E Series - Manual (Page 19)

© 2011 Magnum Energy, Inc.
2.4 Wiring Guidelines
• Before connecting any wires, determine all wire routes to and
from the inverter throughout the caravan, vehicle, or boat.
• Conductors passing through walls or other structural members
must be protected to minimize insulation damage such as chafi ng,
which can be caused by vibration or constant rubbing.
• Always check for existing electrical, plumbing, or other areas of
potential damage prior to making cuts in structural surfaces or
walls.
• Make sure all wires have a smooth bend radius and do not be-
come kinked.
• Both AC and DC overcurrent protection must be provided as part
of the installation.
• Do not attempt to use a vehicle metal frame in place of the nega-
tive connection or DC ground. The inverter requires a reliable
negative and ground return path directly to the battery.
• DC wires and cables should be tied together with wire ties or
electrical tape approximately every 6 inches. This improves the
surge capability and reduces the effects of inductance, which im-
proves the inverter waveform and reduces wear on the inverter’s
fi lter capacitors.
• Only use copper wires with a minimum temperature rating of
75°C.
• To ensure the maximum performance from the inverter, all con-
nections from the battery bank to the inverter should be mini-
mized. The exceptions are the DC overcurrent disconnect in the
positive line.
2.5 DC Wiring
This section describes the MMS-E Series inverter’s required DC wire
sizes, the recommended disconnect/overcurrent protection, and how
to make the DC connections to the inverter and the battery bank.
2.5.1 DC Wire Sizing
It is important to use the correct DC wire to achieve maximum ef-
fi ciency from the system, and to reduce fi re hazards associated with
overheating. Refer to Table 2-1 to select the minimum DC wire size
needed based on your inverter model. If the distance from the in-
verter to the battery bank is greater than three feet, use Table 2-2
to help determine the minimum recommended cable sizes for longer
distances. Always keep your wire runs as short as practical to help
prevent low voltage shutdowns, and to keep the DC breaker from
nuisance tripping (or open fuses) because of increased current draw.
Undersized cables can also lower the inverter’s peak output voltage,
as well as reduce its ability to surge heavy loads.
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2.0 Installation