What is the minimum height requirement for raceways or cables installed on rooftops to avoid needing a temperature adder?

The minimum height requirement for raceways or cables installed on rooftops to avoid needing a temperature adder is 7/8 inches. This specification is derived from industry standards that dictate how cables should be managed in environments where they are exposed to temperature variations, such as rooftops.

By maintaining a clearance of at least 7/8 inches, these installations ensure that air circulation can help to dissipate heat, thus preventing the cables or raceways from reaching excessive temperatures that could affect their performance or longevity. When installations do not meet this height, there may be a need to apply a temperature correction factor to account for the higher temperatures that can occur in rooftop environments, thereby affecting the sizing and performance of the wiring and associated electrical systems.

The specified height helps maintain safety and operational integrity in electrical installations, which is crucial for compliance with relevant codes and practices.