What can be used as a fault current return path if work is to be performed on H-structure type transmission lines?

When performing work on H-structure type transmission lines, overhead ground wires serve as an effective fault current return path. These wires, typically installed at or near the top of transmission structures, are designed to safely carry fault currents away from the energized parts of the line. They provide a crucial protective measure by enabling fault currents to return to the ground in a controlled manner, thereby minimizing the risk of electric shock to workers and avoiding damage to equipment.

Overhead ground wires are particularly advantageous because they are readily accessible and integrated into the transmission line's design. This allows for a consistent and reliable fault return path compared to the other options listed. While underground cables, metal ground rods, and portable generators can have their own uses in electrical systems, they do not serve the specific function required for providing a fault current return path in the context of overhead transmission lines during maintenance operations.