Glossary - SMA SUNNY ISLAND 6048-US Technical Description

SMA America, LLC 23 Glossary

23 Glossary

Absorption phase
Constant voltage phase: A charging phase using constant charging voltage. The charging current
constantly decreases in this phase.
AC
Abbreviation for "Alternating Current"
AC coupling
The AC side connection between loads, generators and storage devices.
AGM battery
Absorbent glass mat separator battery. This is a battery where the electrolyte (a mixture of water and
sulfuric acid) is bound to a glass fiber mat. This is a type of a sealed or valve regulated lead-acid
(VRLA) lead-acid battery. A gas mixture (hydrogen and oxygen) is always generated when lead-acid
batteries are charged, and in normal operation this internally recombines to form water. This removes
the need for regularly refilling the battery cells with water, which is why these batteries are often
described as "low maintenance" or even "maintenance free". AGM batteries are available from many
different manufacturers for a wide range of applications. They usually have very good high current
properties but are not very charge-cycle resistant in relation to deep discharge.
Ah
Abbreviation for "ampere-hour". Unit of electrical charge, one ampere-hour is the charge provided by
a constant current of 1 A over a period of one hour.
Backup system
Backup systems are power supply systems that provide an extra level of security for standard power
supply systems. The utility grid is usually the standard power supply system and the backup system is
provided by an additional stand-alone grid system in the case of a power outage. In addition to the
backup systems, diesel generators in PV battery systems are also described as backup generators.
They perform the same task here as a backup system for the utility grid.
Battery
A battery is an electrochemical energy storage that can release previously stored chemical energy as
electrical energy. A distinction is made between non-rechargeable batteries (often used in consumer
markets) and rechargeable batteries (accumulators). In stand-alone grid systems, lead-acid batteries
are almost always used and, very rarely, nickel/cadmium batteries are used as secondary
rechargeable batteries.
Technical description SI4548_6048-US-TB_en-13 231