Abstract: A photovoltaic (PV) sub-generator junction box (1) for a PV system (100) comprises a plurality of electric terminals (11) for optionally connecting one respective PV string (2) of one or more serially connected PV modules (3). Said PV sub-generator junction box (1) further comprises a sub-generator line terminal (12) for connecting a PV sub-generator line (4) of a remote central PV inverter (5) or connecting a PV sub-generator line (4) of an inserted PV generator junction box (6). The PV sub-generator junction box (1) also comprises an electronic control unit (10) that is connected to a central control unit (7) of the PV inverter (5) in order to exchange data (DAT0). According to the invention, the PV sub-generator junction box (1) comprises a power line modem (8) for feeding and retrieving the data (DAT) via the PV sub-generator line (4).

Abstract: A photovoltaic (PV) sub-generator junction box (1) for a PV system (100) comprises a plurality of electric terminals (11) for optionally connecting one respective PV string (2) of one or more serially connected PV modules (3). Said PV sub-generator junction box (1) further comprises a sub-generator line terminal (12) for connecting a PV sub-generator line (4) of a remote central PV inverter (5) or connecting a PV sub-generator line (4) of an inserted PV generator junction box (6). The PV sub-generator junction box (1) also comprises an electronic control unit (10) that is connected to a central control unit (7) of the PV inverter (5) in order to exchange data (DAT). According to the invention, the PV sub-generator junction box (1) comprises a power line modem (8) for feeding and retrieving the data (DAT) via the PV sub-generator line (4).

Abstract: A method for recognizing the theft of at least one photovoltaic module of a PV system. The PV system comprises at least one string of serially connected PV modules for supplying a field voltage, where the at least one string is connected in parallel and the PV modules each have a plurality of serially connected PV cells. In addition, bypass diodes connected in an anti-parallel manner are provided for protecting the PV cells. During a non-charging operation, i.e., the evening and at night, a test voltage that is negative relative to the field voltage is connected to the at least one PV string to adjust a test current through the bypass diodes. A theft message is automatically output when at least one of the test current and the test voltage significantly change.