©
2013 Magnum Energy, Inc.
Page 41
Operation
3.11.2 Parallel System Connections and Components
The basic installation procedure of the parallel system is similar to that of a single inverter system.
However, the AC and DC connections and components required in the parallel system must be
considered.
3.11.2.1
AC and DC Connections Simplifi ed Using Magnum Panels
The AC and DC connections in the parallel system depend upon other components (noted in the
two sections below in
bold
), but are simpli
fi
ed when using the Magnum Panel (MP-E & MMP-E)
Series of enclosures. As shown in Figure 3-6, the AC panel and DC panel—which are part of the
MP-E & MMP-E Series enclosures—provide these separate components; and the speci
fi
c AC or DC
wiring to these components are completed for you. Figures 3-7 and 3-8 are simpli
fi
ed diagrams
of the AC and DC panels showing the connections and components.
3.11.2.2
AC Connections Required in Parallel System
The AC input supply to the parallel system must be a 230 VAC system that provides one line
conductors, a neutral, and a ground. Each MS-PE inverter requires a single-pole circuit breaker
rated for a maximum 30A. Typically the AC supply originates in a main distribution panel, providing
the separate
AC breakers
required for the AC input of each MS-PE inverter. This main panel also
has to provide the
AC busbars
to allow connection of the neutral and ground conductors to each
inverter input.
The AC output side of the parallel system requires an electrical panel—referred to as the inverter
panel—that combines all the inverter outputs and is equipped with a large circuit breaker rated for
the total output current of the parallel system. This inverter panel must provide the
AC busbars
for the neutral and ground conductors from each inverter output.
If the inverter system requires isolation from the AC source for servicing without losing power to
the AC loads, an
AC bypass
should be installed between the AC input and output connections.
3.11.2.3
DC Connections Required in Parallel System
When inverters are stacked they must operate from a common battery bank. In other words, the
DC negative of one inverter must be common with the second inverter and likewise for the DC
positive. Each inverter must be wired to the single battery bank separately and have a
DC breaker
in the positive side, matched to the cable size.
All DC negatives are required to be combined on a
DC busbar
and if the system requires battery
bank monitoring, a full system
DC shunt
will need to be installed in the DC negative side.
DC
BREAKERS
DC BREAKERS
(1 – 4)
MAS SL1 SL2 SL3
O
PTION
MP-E SERIES
(DC PANEL)
MS-PE INVERTERS
(1 - 4)
POS
NEG
DC
SHUNT
DC
BUSBARS
DC
BUSBARS
DC LOADS
(Customer Connection)
DC SOURCE
(Customer Connection)
NEG
POS
AC
BYPASS
OFF
ON
INVERTER
BUSBAR
MP-E SERIES
(AC PANEL)
MS-PE INVERTERS
(1 - 4)
IN
OUT
AC LOADS
(Customer Connection)
AC SOURCE
(Customer Connection)
AC
BUSBARS
AC
BUSBARS
AC BREAKERS
(1 – 4)
MAS SL1
SL2
SL3
Figure 3-7, Simplifi ed Magnum Panel
(AC Panel)
Figure 3-8, Simplifi ed Magnum Panel
(DC Panel)
