What is the purpose of strung bare ground wire over underground cables?

The purpose of strung bare ground wire over underground cables is primarily to trace the circuit or to gather stray current. This practice enhances safety by providing a path for any unwanted electrical currents that might otherwise disrupt the intended circuit, adding a layer of security against potential faults. Additionally, having a bare ground wire allows technicians or electricians to easily identify or trace the circuit lines, which is critical in maintenance and troubleshooting tasks.

While the other options might seem plausible, they do not accurately reflect the primary function of the ground wire in this context. Powering cables would not require a bare ground wire overhead; rather, cables are typically powered through their insulated conductors. Preventing overheating is generally managed through proper cable sizing and insulation ratings, rather than with an external ground wire. The idea of a signaling device does not align with the established norms of electrical systems, as signaling devices typically involve more complex components such as relays or sensors. Thus, the correct choice emphasizes the importance of safety and traceability in electrical circuits.