This scheme serves to test the continuity of a cableelectric, but cannot be linkedelectricity  of 220V, so we will have to use two devices, one with a 9V battery, and another  that has to receive the same 9V voltage.

      Put onebeetle  that makes a sound when the 9V voltage passes, also lights up a flashing red led, when this  is used  during the day led may not be seen, so a beetle was placed to imitate the beep sound.

      This way we will know if the cable is broken or not and which cable is intended.