SMA Sunny Island 4248U, Инструкция по установке и эксплуатации

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SI4248U Manual User Manual
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Sunny Island Applications
Off-Grid / Stand Alone Systems
By definition, off-grid or stand alone systems are systems where electrical power is generated
and stored without assistance from the utility grid. These systems typically consist of one or
more power generation sources such as a PV array, a wind generator, a hydro-electric
generator or a gas powered generator.
Typically, there is a need to store the power that is generated. Without a storage method,
power would only be available when one or more of the generating devices were active. (i.e.
when the sun was shining for a PV array, or when the wind was blowing for a wind generator.)
Batteries are the most common device used for power storage. The size and type of batteries
used depends greatly on the system power requirements.
Because many of the loads that will be powered by the system require AC power as opposed
to DC power, an inverter is needed to change the DC voltage to an AC voltage that can be
used by the AC loads. This is exactly what the Sunny Island 4248U was designed to do.
The Sunny Island 4248U can also function as a battery charger for charging the battery bank.
This mode operates by connecting an AC power source to the inverter’s AC power input. The
AC power source could be a gas powered generator or even the utility grid, if available at the
system’s location. The power generated by the external source can be used to power AC loads
via the Sunny Island 4248U while the batteries are being charged at the same time. The Sunny
Island 4248U watches the battery voltage and only applies the amount of power necessary to
bring the batteries up to a full state of charge after all power required by the loads is supplied.
Back-Up Systems
A back-up system is configured differently from an off-grid system. The purpose of a back-up
system is to supply power when the primary source of electrical power, such as the utility grid,
fails for some reason. When used as a back-up system, the Sunny Island 4248U is designed
to begin providing AC power automatically whenever the primary source of AC power shuts
down.
In a back-up configuration, the Sunny Island 4248U still requires a source for its power. This
is accomplished through the use of a large battery bank. Again, the size and type of batteries
used will be determined by the intended operation of the system.
During times of normal operation where the primary source of AC power is active, the Sunny
Island 4248U maintains the charge of the battery bank so that they are ready in the event of
an outage. The Sunny Island 4248U applies a sophisticated charging algorithm to ensure that
full charge capacity is maintained and that the life of the battery bank is maximized.
The Sunny Island 4248U also has the ability to connect external sources of power, such as a
gas powered generator to assist in powering the loads and charging the battery bank during
extended outages.