Methods of operating a communication node are provided. A method of operating a communication node may include transmitting a first power line communication signal from the communication node to a sensor device that is at or adjacent an electric grid device. The method may include receiving from the sensor device a second power line communication signal that is responsive to the first power line communication signal, at the communication node. Moreover, the method may include determining a distance between the communication node and the electric grid device by measuring an electrical parameter of the second power line communication signal, at the communication node. Related communication nodes are also described.