What is required to identify each service disconnecting means?

To ensure safety and clarity in electrical installations, each service disconnecting means must be marked permanently. This requirement establishes a clear identification system, allowing anyone working on or inspecting the electrical system to easily locate and understand the functions of the disconnecting means. Permanent marking is crucial as it helps emergency personnel and maintenance workers quickly identify the disconnect, which can be vital during emergencies or during routine inspections and repairs.

The marking should be durable and legible for the lifespan of the equipment, ensuring that the identifying information is not lost or obscured over time. This permanence is essential for maintaining safety standards and compliance with the National Electrical Code (NEC).

Other options, while they might pertain to equipment safety or identification in some contexts, do not fulfill the requirement of permanent identification as specified in the NEC.