SMA Sunny Island 3324, User Manual, Page: 69 / 80

SMA Technologie AG Glossary
User Manual SI3324/4248-14:FE2406 Page 155
Charge mode
See Battery charging mode
C-rate
The nominal capacity specification is always provided with the discharge time on
which the capacity is based. The nominal capacity is the product of the constant
charging current I
N
and the discharge time t
N
, that passes between commencement
of discharging the fully charged battery until the final discharge voltage V
S
is
reached. In permanently on-site batteries, the C10 capacity is usually specified. i.e.
a battery with C
10
= 200 Ah can be discharged for 10 hours at a nominal current of
0.1 × C
10
= I
10
= 20 A.
DC
Abbreviation for "Direct Current"
Derating
A controlled reduction in performance, usually dependent on component
temperatures. Derating is used instead of performing a complete shutdown of the
system.
DSP
Abbreviation for Digital Signal Processor. A DSP is a microprocessor chip especially
developed for digital signal processing and control.
Electrolyte
Allows the conduction of ions within a battery. In lead acid batteries, the electrolyte
is diluted sulfuric acid and is also a reactant in the electrochemical reaction. Nickel/
Cadmium batteries use an alkaline electrolyte (potassium hydroxide).
EPROM
See Flash EEPROM
Equalize charge
Equalize charge: Allows multiple series-connected battery cells to be charged to a
unified charge level of 95 – 100 %. Without regular equalization charging, the
charge states of the various cells slowly drift apart, which can lead to premature
battery bank failure.
Firmware
Firmware is software that is stored in a chip in various electronic devices, such as
Sunny Island, hard disk recorders, DVD burners and players, newer television sets,
household appliances and computers - in contrast to software that is stored on a hard
drive, CD-ROM or other media. These days, firmware is usually stored in Flash
memory or an EEPROM.