Reference is now made to FIG. 10, illustrating a system 1000 according to other embodiments of the present invention for protection during an islanding condition. For simplicity, a single string 1023 is shown of distributed power sources, e.g. solar panels 201 a-201 d connected to respective power converters 1005 a-d. Serial string 1023 is input to inverter 1004 through wires 412 and 410. The output of inverter 1004 is connected to and supplies electrical power to the electrical grid. Inverter 1004, typically includes a monitoring and detection mechanism 701 which monitors one or more parameters of the electrical grid such as voltage and/or frequency. If one or more of the grid parameters is out of specification indicating an islanding condition, monitoring, and detection mechanism 701 typically shuts down inverter 1004 or disconnects inverter 704 from the grid so that output power is no longer supplied by inverter 1004 to the grid. During normal operation, a wireless transmitter 1003 transmits wirelessly a signal, for instance between 100 Megahertz-10 Gigahertz.

Reference is now also made to FIG. 10A which illustrates converter 1005 in more detail. The wireless signal is received and constantly monitored by a wireless receiver 1007 Only while receiver 1007 senses the wireless signal does receiver 1007 provide an enable signal to controller 306. When controller 306 doesn't receive an enabling signal from receiver 1007, controller 306 shuts down power conversion of converter 1005.