What type of equipment is addressed in Article 647?

Article 647 of the National Electrical Code (NEC) specifically focuses on the requirements for sensitive electronic equipment. This includes devices that require special considerations regarding power quality, grounding, and circuit design to function properly without interference or interruption. The intent of the article is to ensure that installations are designed to minimize electromagnetic interference (EMI) and provide a suitable operating environment for electronic devices that could be adversely affected by electrical disturbances.

Sensitive electronic equipment encompasses a wide range of devices, including computers, telecommunications equipment, and medical devices, among others. These types of devices tend to be more susceptible to voltage fluctuations, surges, or other electrical irregularities, which can lead to improper operation, malfunctions, or damage.

While the other options refer to specific technologies or equipment, they do not align with the focus of Article 647. Solar photovoltaic systems, for instance, are covered under different articles that pertain directly to energy generation and installation requirements. Similarly, X-ray equipment has its own guidelines related to safety and operational standards and does not revolve around the principles outlined in Article 647. Induction heating equipment also falls outside the scope of sensitive electronic equipment, as it operates under different electrical dynamics and does not specifically require the same considerations for protection against interference.