Owner`s manual

© 2010 Magnum Energy, Inc.Page 16
3.0 Installation
3.5 Wiring the MMP Enclosure - General Requirements
This section also describes the requirements and recommendations for the electrical wiring to the
MMP enclosure. Read all instructions before wiring the MMP enclosure.
All wiring should meet all local codes and standards and be performed by qualifi ed
personnel such as a licensed electrician.
The NEC (National Electric Code, ANSI/NFPA 70) for the United States and the CEC (Canadian
Electrical Code) for Canada provide the standards for safely wiring residential and commercial
installations. The NEC/CEC lists the requirement for wire sizes, overcurrent protection and
installation methods and requirements.
The MMP enclosure/Inverter systems involve power from multiple sources (inverter, generator,
utility, batteries, solar arrays, etc.) which make the wiring more hazardous and challenging.
WARNING: The AC neutral and DC negative are bonded to ground in this enclosure.
If the AC or DC circuits are already bonded to ground elsewhere in your system, you
must remove the DC and/or AC bonding inside this enclosure. Refer to Section 3.11
and 3.12 to remove the AC and/or DC ground bond connection.
WARNING: Ensure all sources of DC power (i.e., batteries, solar, wind, or hydro) and
AC power (utility power or AC generator) are de-energized (i.e., breakers opened,
fuses removed) before proceeding - to prevent accidental shock.
3.5.1 Disconnect Switch and Overcurrent Protection
For residential and commercial electrical systems, the NEC/CEC requires a disconnect switch and
overcurrent protection on all ungrounded conductors in the AC side as well as the DC side. The
MMP enclosure provides both AC and DC circuit breakers that are used as the disconnect switch.
These circuit breakers can also be used as the overcurrent protection device when the ampacity
of the wire, its insulating material, voltage, and temperature rating are correctly sized to the DC
circuit breakers in your MMP enclosure. Refer to the appropriate installation section (AC Wiring or
DC Wiring) to determine the minimum recommended wire size required.
3.5.2 Wiring Requirements
The AC and DC wires into and out of the MMP enclosure must be protected as required by code.
This can be done by using jacketed wires or by feeding the wires through conduit.
Info: If using a Magnum inverter, and the AC wires are individual conductors (i.e., not
jacketed), the strain reliefs on the inverter can be replaced with 3/4” grommets.
Use proper clamps, or other approved methods for securing the cable/conduit to the enclosure.
Do not mix AC and DC wiring in the same conduit. The MMP enclosure is specifi cally approved/
designed for both AC and DC wiring. However, where DC wiring must cross AC or vice-versa,
try to make the wires at the crossing point 90° to one another.
Use only copper wires with a minimum rating of 150V, 75°C if only 120VAC power is being
used; or with a minimum rating of 300V, 75°C if 120/240VAC power is being used.
In a system where one conductor is grounded the wire colors on the DC side and AC side are the
same. The insulation on all grounded conductors (DC negative/AC neutral) must be white, gray,
or any color except green if marked with white at each termination (marking only allowed on 6
AWG or larger conductors). The equipment grounding conductors must be bare (no insulation),
or have green or green with yellow-striped insulation or identifi cation. The hot-ungrounded
conductor (DC positive/AC hot) is usually red or black.
Terminals containing more than one conductor must be listed for multiple conductors.
The connectors or terminals used on fl exible, fi ne-stranded conductors must be specifi cally
marked or labeled for use with fi ne-stranded conductors.
The MMP enclosure includes wires (along with communication cables) with insulation rated
for at least 300 volts to allow 120/240 VAC inverters to be installed. If installing a 120/240
VAC inverter, the installer must also provide wires (both power and communication) with the
insulation rated for at least 300 volts.
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