SMA SC 9000TL - Manual (Page 19)

SMA Solar Technology AG Glossary
User Manual SMC9-11TLRP-BA-BEN111320 19
8 Glossary
AC
Abbreviation for "alternating current".
DC
Abbreviation for "direct current".
Derating
A controlled reduction in performance, usually dependent on component temperatures.
Electronic Solar Switch (ESS)
The Electronic Solar Switch is part of the DC disconnection unit of the inverter. The Electronic Solar
Switch must be securely inserted into the bottom of the inverter and must only be removed by an
electrically skilled person.
MPP (Maximum Power Point)
Operating point of the inverter from current/voltage of the PV array. The actual position of the MPP
changes constantly, depending on the level of radiation and cell temperature.
PV
Abbreviation for "photovoltaics".
Reactive Power Control
Inverters with Reactive Power Control are inverters capable of utilizing reactive power. By setting a
default value for the displacement factor (cos φ), they can feed reactive power to the grid.
SMA Power Balancer
The SMA Power Balancer is a serial feature of the Sunny Mini Central. The SMA Power Balancer
prevents the formation of an unbalanced load > 5 kVA (in Italy > 6 kVA) during 3-phase feed-in. To
this effect, 3 Sunny Mini Centrals are connected via a control line to a 3-phase feed-in unit.
Unbalanced load
The unbalanced load is the difference between the power fed into the grid at the individual phase
conductors. In Germany, this must not exceed 5 kVA. In Italy, the unbalanced load is restricted to
6 kVA.
Varistor
The varistors protect the electronics in the inverter from atmospherically coupled energy peaks, such
as those that can occur when lightning strikes nearby.