Which article discusses general principles related to equipment over 1000 volts?

The correct answer is found in Article 490, which deals specifically with the requirements and general principles related to electrical equipment operating at voltages over 1000 volts. This article outlines the necessary safety measures, installation requirements, and operation standards to ensure safety and compliance when dealing with high-voltage equipment.

Understanding the significance of Article 490 is crucial because working with equipment at this voltage level poses increased risks, requiring more stringent regulations to maintain safety for both workers and the general public. The inclusion of specific guidelines helps electricians ensure that installations are done properly and that all safety standards are adhered to, reducing the risk of accidents.

In contrast, the other articles mentioned focus on other aspects of the electrical code or various types of equipment that do not pertain specifically to voltages exceeding 1000 volts, thus making them less relevant in this context. This highlights why Article 490 is the key reference for general principles regarding high-voltage equipment.