What characteristic should distribution systems have according to guidelines?

The appropriate characteristic for distribution systems, according to guidelines, is that they should be fully insulated and ungrounded. This approach mitigates the risk of electrical shock and system failures by ensuring that all electrical components are insulated from unintended contact and that no current can flow to the ground. This insulation protects both the equipment and users, maintaining operational safety under various conditions.

Fully insulated systems contribute to reliability and efficiency in electrical distribution, minimizing the chance of ground faults and other electrical malfunctions. An ungrounded system also allows you to identify potential issues more effectively because, with proper insulation, the failure of a single component won't lead to a system-wide failure or hazards.

Other options, such as partially grounded or minimal insulation, introduce risks associated with electrical shock and system instability, while single-phase ungrounded configurations may not provide the same level of protection or reliability required in modern electrical distribution standards. Choosing a fully insulated and ungrounded system aligns with best practices for safety and operational integrity in electrical distribution.