Which of the following best describes an isolated ground?

An isolated ground refers to a grounding system designed to provide a unique ground path for electrical devices, distinct from the building grounding system. This method is utilized primarily to reduce electrical noise, minimize interference, and enhance equipment performance, especially for sensitive devices in environments like hospitals or data centers. By having a separate ground path, the isolated ground helps to ensure that any electrical surges or disturbances do not affect other systems within the building, thus enhancing safety and operational reliability.

In contrast, the other options do not accurately capture the concept of an isolated ground. A system without any grounding connection would pose significant safety hazards due to electrical faults. A grounding system that is connected to the building ground does not qualify as isolated, as it participates in the common grounding scheme, which may not adequately prevent interference. Additionally, a system using reinforced cable does not inherently relate to ground isolation; rather, it refers to the physical construction of cables, not the grounding methodology.