Mitsubishi Electric PV-PNS04ATL-GER Operation Manual page 88

(5) Block diagram
The block diagram for the PV inverter is shown below.
From grid
Main relay
Grid relay
DC/AC
PV module
string
PV module PV module
string string
Controller 2
Grid voltage, Frequency monitoring,
Impedance monitoring,
DC effluence detect,
Earth fault detect
Controller 1
Grid voltage, Frequency monitoring,
Impedance monitoring,
DC effluence detect,
Earth fault detect
86
PV Inverter
Power switch
Stop⇔Run
Display