SMA America, LLC
Glossary
Technical Description
SI5048U-TUS121440
221
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 discharging current IN and the discharge
time tN, that passes between commencement of discharging the fully charged battery until the final
discharge voltage VS is reached. In permanently on-site batteries, the C10 capacity is usually
specified. i.e. a battery with C10 = 200 Ah can be discharged for 10 hours at a nominal current of
0.1 x C10 = I10 = 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
A chemical solution that 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 state of
charge of 95 – 100 %. Without regular equalization charging, the state of charges of the various
cells slowly drift apart, which can lead to poor battery performance and 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, CDROM or other media. These
days, firmware is usually stored in Flash memory or an EEPROM chip.
FLA
Flooded Lead Acid battery: A lead acid battery with liquid electrolyte, also often described as a
sealed lead acid battery.
