Optional standby systems are covered in _____.

Optional standby systems are covered in NEC Article 702. This article provides guidelines and requirements for optional standby systems, which are designed to supply power to critical loads when the normal power sources are unavailable, in a way that enhances safety and efficiency. These systems include equipment and wiring that serve to provide power during outages, which might not be considered life-sustaining but still serves important functions for facilities.

In contrast, the other articles address different types of systems. Article 700 focuses on emergency systems, which are required to operate automatically to protect lives and property during emergency situations. Article 701 refers to legally required standby systems that ensure power for specific essential loads when normal power fails. Article 703 discusses the requirements for transfer equipment that can be utilized across different sources, but it does not specifically address optional standby systems. Thus, understanding these distinctions is crucial when choosing appropriate code sections related to power supply systems in various applications.