A disconnecting means must be marked by what?

The correct answer highlights the requirement for a disconnecting means to be marked with an identification plate or panelboard schedule. This is crucial for safety and operational efficiency, as it provides essential information about the electrical system. An identification plate or panelboard schedule helps in identifying the specific function and load served by the disconnecting means, enabling technicians and maintenance personnel to work safely and effectively on the electrical system.

Having this clear marking is important for several reasons. It ensures that anyone working on or around the electrical equipment can quickly identify the correct disconnecting means, which is vital in preventing accidental energization during maintenance or repairs. This identification helps maintain a safe working environment and ensures compliance with electrical codes and regulations.

While warning labels, manufacturer’s names, and operator instructions may provide useful information, they do not fulfill the specific requirement of identifying the disconnecting means as effectively as an identification plate or panelboard schedule does. Such markings are essential for not only safety but also for effective management of electrical systems in accordance with the National Electrical Code (NEC) and local regulations.