SMA SB 3300-11 - Manual (Page 19)

SMA Solar Technology AG Glossary
User Manual SB33_38-BA-BEN114230 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 inverter DC disconnection unit. The Electronic Solar Switch
must be securely inserted into the bottom of the inverter and may only be removed by an electrically
qualified person.
MPP (Maximum Power Point)
Operating point of the inverter derived from current/voltage of the PV array. The actual MPP changes
constantly, depending on the level of irradiation, the cell temperature, etc.
PV
Abbreviation for photovoltaics.
Varistor
The varistors protect the electronics in the inverter from atmospherically coupled energy peaks, such
as may occur when lightning strikes nearby.