SI4548-US-10 Manual

SMA America, LLC 23 Glossary
Technical description SI4548_6048-US-TB_en-13 237
PV module
Electrical connection of several PV cells encapsulated in an enclosure to protect the sensitive cells from
mechanical stress and environmental influences.
PV plant
Describes a PV plant for generating electrical power. Describes the totality of components required
for the exploitation and utilization of solar energy. In grid-tie plants this includes not only the PV array,
but also the inverter, e.g. Sunny Boy or Sunny Mini Central.
Series connection
In this case the positive pole of each battery is connected to the negative pole of the next battery.
There is only one circuit where current can flow. Series connection increases the voltage of the entire
battery storage system. If four 12 V batteries with a capacity of 100 Ah each are connected in series,
the total voltage is 4 × 12 V = 48 V, while the total capacity remains at 100 Ah.
Sealed lead acid battery
A type of battery in which the electrolyte (a mixture of water and sulfuric acid) is bound into a gel.
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" (see also AGM batteries). SLA batteries are available from many different
manufacturers for a wide range of applications. There are gel batteries for high current applications
but also for cycle operation with very high deep discharge cycle resistance.
Self discharge
Loss of battery charge while it is stored or not used. A higher ambient temperature has a strong
influence on self discharge.
SOC
State of Charge: the state of charge of the battery, see State of charge. If (e.g.) 25 Ah is taken from
a 100-Ah battery, the state of charge (SOC) is then 75%.
Solar energy
"Solar energy", this means energy from sunlight or other solar irradiation (heat and/or UV radiation).