Reference is now also made to FIG. 4B which illustrates in more detail signaling mechanism 420. Signaling mechanism 420 includes a relay 428 which is normally open and controlled by a microcontroller 422. Relay 428 is switched at a given rate, e.g. 100 Hz, and the signal is superimposed by action of relay 428 onto serial string 423 over wires 410 and 412. Microcontroller 422 typically provides the control of the signal, e.g. 100 Hz, during normal operation of distributed power system 40. Microcontroller 422 is typically connected to one or more sensors in order to monitor the operation of inverter 104. In the example of FIG. 4B, microcontroller 422 monitors over-voltage of the input DC voltage to inverter 104. The example shown in FIG. 4B includes an input DC voltage tap 432 connected to an analog to digital converter (A/D) 430, the output of which is provided to microcontroller 422. The tap 432 may be, e.g., a Hall-effect sensors, series connected resistor across which the voltage drop is measured, etc. In one embodiment, an over-voltage condition as measured by microcontroller 422, results in microcontroller 422 stopping the signaling through relay 428 and/or opening one or more protective relays 424, 426 in series with the input DC voltage to inverter 104. Note that one switch 424 or 426 may be enough for performing the required action, and two switches in series are shown solely for the purpose of illustration that double protection might be required by some regulatory bodies. A power management block 434 taps voltage for powering microcontroller 422 and any other active electronics components (not shown) in block 420.