Which equipment category is described by Article 647?

Article 647 of the National Electrical Code (NEC) specifically deals with the installation and requirements for sensitive electronic equipment. This category encompasses a wide range of devices and systems that require a controlled environment to prevent disruption from electrical noise and other interferences, which is crucial for their proper functioning. Sensitive electronic equipment includes devices such as computers, communication systems, and other electronic apparatus that can be adversely affected by electrical disturbances.

The article outlines the necessary measures to ensure that these types of equipment are properly installed and maintained to minimize any potential impact from electrical interference, ensuring operational reliability and safety. By focusing on standards specific to sensitive electronics, this section of the NEC provides guidance that is essential for maintaining the integrity of these critical devices in various applications.

The other categories listed do not align with the focus of Article 647; they pertain to different aspects of electrical systems and equipment. For instance, audio signal processing equipment, electric vehicle charging systems, and electrolytic cells are covered under different articles within NEC that address unique requirements and standards applicable to those specific types of equipment and applications.