Abstract: A photovoltaic, PV, module level monitoring system (1) comprising a photovoltaic array (PVA) including at least one photovoltaic string (PVS) comprising photovoltaic modules, PVM, (5) each having a module level device, MLD, (4) adapted to monitor and/or to control the associated photovoltaic module, PVM, (5), wherein each module level device, MLD, (4) comprises a transceiver adapted to communicate with a transceiver of a base station (2) of an inverter (6) connected to said photovoltaic array (PVA), wherein the transceivers are coupled by associated duplexer circuits (7) to a DC power network comprising power cables (3) connecting the photovoltaic modules, PVM, (5) of the at least one photovoltaic string (PVS) of said photovoltaic array (PVA) with the base station (2) of the inverter (6), wherein a signal amplitude of a communication signal, CS, transmitted by a transceiver via its associated duplexer circuit (7) is adjusted automatically depending on a monitored impedance, ZPV, of the respective photovoltaic

Abstract: The aim of the invention is to detect an arc in an assembly for transmitting a direct voltage. This aim is achieved by a communication transformer having a primary winding and a secondary winding, the secondary winding being connected to a transmitting device, which is designed to impress a communication signal onto the secondary winding of the communication transformer, and the primary winding being connected to one of the direct voltage lines in order to feed a communication signal transformed by the communication transformer to one of the direct voltage lines. In order to detect, in the assembly, the arc signal caused by an arc, the secondary winding is connected to an arc detection unit, which is designed to detect an arc signal transformed by the communication transformer.

Abstract: To recognize a fault in an arrangement including a transformer having a primary winding connected in series with a DC voltage line and a secondary winding coupled magnetically to the primary winding, and including an evaluation unit that processes a secondary signal on the secondary winding, a signal component at at least one frequency is determined from the secondary signal and a signal level of the signal component is compared with a signal threshold. The fault is detected when the signal level falls below the signal threshold.

Abstract: The aim of the invention is to detect an arc in an assembly for transmitting a direct voltage. This aim is achieved by a communication transformer having a primary winding and a secondary winding, the secondary winding being connected to a transmitting device, which is designed to impress a communication signal onto the secondary winding of the communication transformer, and the primary winding being connected to one of the direct voltage lines in order to feed a communication signal transformed by the communication transformer to one of the direct voltage lines. In order to detect, in the assembly, the arc signal caused by an arc, the secondary winding is connected to an arc detection unit, which is designed to detect an arc signal transformed by the communication transformer.

Abstract: A photovoltaic, PV, module level monitoring system (1) comprising a photovoltaic array (PVA) including at least one photovoltaic string (PVS) comprising photovoltaic modules, PVM, (5) each having a module level device, MLD, (4) adapted to monitor and/or to control the associated photovoltaic module, PVM, (5), wherein each module level device, MLD, (4) comprises a transceiver adapted to communicate with a transceiver of a base station (2) of an inverter (6) connected to said photovoltaic array (PVA), wherein the transceivers are coupled by associated duplexer circuits (7) to a DC power network comprising power cables (3) connecting the photovoltaic modules, PVM, (5) of the at least one photovoltaic string (PVS) of said photovoltaic array (PVA) with the base station (2) of the inverter (6), wherein a signal amplitude of a communication signal, CS, transmitted by a transceiver via its associated duplexer circuit (7) is adjusted automatically depending on a monitored impedance, ZPV, of the respective photovoltaic

Abstract: To recognize a fault in an arrangement including a transformer having a primary winding connected in series with a DC voltage line and a secondary winding coupled magnetically to the primary winding, and including an evaluation unit that processes a secondary signal on the secondary winding, a signal component at at least one frequency is determined from the secondary signal and a signal level of the signal component is compared with a signal threshold. The fault is detected when the signal level falls below the signal threshold.

Abstract: The aim of the invention is to detect an arc in an assembly for transmitting a direct voltage. This aim is achieved by a communication transformer having a primary winding and a secondary winding, the secondary winding being connected to a transmitting device, which is designed to impress a communication signal onto the secondary winding of the communication transformer, and the primary winding being connected to one of the direct voltage lines in order to feed a communication signal transformed by the communication transformer to one of the direct voltage lines. In order to detect, in the assembly, the arc signal caused by an arc, the secondary winding is connected to an arc detection unit, which is designed to detect an arc signal transformed by the communication transformer.

Abstract: Power transmission system (1) for power transmission of electric power (P) from a power source (2A) to a power sink (4A) which is connected to the power source (2A) via a power transfer cable (3), wherein the power source (2A) has a first pole with a first electric potential, which is connected via parallel current lines of a first conducting pair of the power transfer cable (3) to a first pole of the power sink (4A), and a second pole with a second electric potential, which is connected via further parallel current lines of a second conducting pair of the power transfer cable (3) to a second pole of the power sink (4A), wherein, during the power transmission via the current lines, a user data signal can be transmitted between the power source (2A) and the power sink (4A) via at least one conducting pair with current lines of the same electric potential, uninfluenced by the power transmission.

Abstract: For a simple and reliable data communication in an arrangement composed of a plurality of inverters (31, 32, . . . 3n) connected in series and a network monitoring unit (5) it is provided that the network monitoring unit (5) superimposes a synchronization pulse (10) to the network voltage (VN) applied to the electrical load (4), which synchronization pulse can be detected by the inverters (31, 32, . . . 3n) for temporal synchronization.

Abstract: Power transmission system (1) for power transmission of electric power (P) from a power source (2A) to a power sink (4A) which is connected to the power source (2A) via a power transfer cable (3), wherein the power source (2A) has a first pole with a first electric potential, which is connected via parallel current lines of a first conducting pair of the power transfer cable (3) to a first pole of the power sink (4A), and a second pole with a second electric potential, which is connected via further parallel current lines of a second conducting pair of the power transfer cable (3) to a second pole of the power sink (4A), wherein, during the power transmission via the current lines, a user data signal can be transmitted between the power source (2A) and the power sink (4A) via at least one conducting pair with current lines of the same electric potential, uninfluenced by the power transmission.

Abstract: For a simple and reliable data communication in an arrangement composed of a plurality of inverters (31, 32, . . . 3n) connected in series and a network monitoring unit (5) it is provided that the network monitoring unit (5) superimposes a synchronization pulse (10) to the network voltage (VN) applied to the electrical load (4), which synchronization pulse can be detected by the inverters (31, 32, . . . 3n) for temporal synchronization.

Abstract: The invention relates to a method and an apparatus for performing a switching operation with the aid of a operation element (13). In order to avoid mechanical components, at least one light-emitting diode (14) is used as the operating element (13), and the voltage (U) on the at least one light-emitting diode (14) is measured in the switched-off state, and the switching operation is performed when the measured voltage (15) falls below a pregiven lower threshold (18) over a pregiven time period (19).

Abstract: The invention relates to a method and an apparatus for performing a switching operation with the aid of a operation element (13). In order to avoid mechanical components, at least one light-emitting diode (14) is used as the operating element (13), and the voltage (U) on the at least one light-emitting diode (14) is measured in the switched-off state, and the switching operation is performed when the measured voltage (15) falls below a pregiven lower threshold (18) over a pregiven time period (19).