SMA SI 4548-US - Manual (Page 16)

2 Sunny Island 4548-US / 6048-US SMA America, LLC
16 SI4548-6048-US-BE-en-20 Operating Manual
2 Sunny Island 4548-US / 6048-US
2.1 Properties
The Sunny Island is a bidirectional inverter (battery inverter and battery charger) for off-grid systems.
The Sunny Island supplies loads on the stand-alone grid side and charges the batteries with the
energy from grid-feeding units connected on the AC side.
The comfortable support of AC and DC coupling, as well as the expandability of the systems formed
with the Sunny Island guarantee highest flexibility. In addition, innovative technology allows the
Sunny Island to achieve a maximum efficiency of more than 95%. Optimized for partial load
operation, it impresses with low open-circuit and standby consumption. Due to the high overload
capacity and the integrated output management, there is no need to oversize the Sunny Island.
The operation of up to three devices in a single-phase parallel system, of three devices in a
three-phase system or of up to four devices in a double split-phase system enables the Sunny Island
to establish off-grid power supply systems with a power of between 2 kW to 24 kW. In Multicluster
systems, powers of up to as much as 100 kW are possible. Thanks to its sophisticated generator
management, the Sunny Island can control connected diesel generators in a particularly low-stress
and fuel-saving manner. The utility grid can also be integrated. The Sunny Island can also deactivate
loads automatically if the battery does not provide sufficient electrical energy.
The critical component of the off-grid system, the battery, is diligently monitored and optimally utilized.
For lead-acid batteries, the intelligent battery management of the Sunny Island precisely records the
state of charge of the battery. This makes an improved utilization of the battery capacity possible,
which also means that smaller and thus more cost-effective batteries can be used without affecting
performance. The Sunny Island also offers an interface to integrate the external battery management
of lithium-ion batteries.
In order to prevent premature aging caused by incorrect charging and frequent deep discharge, the
Sunny Island has an intelligent charge control and reliable deep-discharge protection. Thanks to these
functions, the battery life can be greatly extended in comparison with simpler devices.
Despite its complex functioning, the Sunny Island is easy to configure. All the settings required for
operation can be quickly and easily configured in a few steps using the Quick Configuration Guide
(QCG). By employing the concept of central operation referred to as "Single Point of Operation", the
system/cluster parameters are only set on the master device, and all other devices automatically
adopt the configuration. The easy-to-understand menu navigation allows quick access to all important
data, even while the system is running. An SD memory card offers an easy system control and
facilitates servicing.
The Sunny Island monitors the set voltage and frequency limits on the utility grid and generator. If
these limits are not observed, it disconnects from the external source without interruption and changes
to stand-alone mode.
Saving data and events
Always use the SD memory card to save data and events. In case of a failure SMA can thus
help you quickly.