What is the primary requirement for grounding in the outdated approach discussed?

The primary requirement for grounding in the outdated approach is three ground cables reaching from line conductors to ground. This design aligns with traditional grounding standards, which aimed to ensure that the electrical system has adequate paths to dissipate fault currents safely, minimizing the risk of electrical shock or equipment damage.

Using three ground cables provides a level of redundancy while maximizing the reliability of the grounding system. This configuration helps in managing fault conditions more effectively, by ensuring that multiple paths exist for fault current to be directed safely into the ground.

The presence of three ground cables reflects the practice of ensuring effective grounding for various potential fault scenarios, thus enhancing the overall safety of the electrical system.