Final answer:
When installing fiber optic cable in a conduit, the maximum fill ratio as outlined by the National Electrical Code must be observed to prevent cable damage and maintain performance. While the numerical aperture involves light acceptance, the conduit fill ratio concerns the physical space allocated to the cables.
Step-by-step explanation:
When preparing to install a fiber optic cable in conduit, technicians must be aware of the maximum fill ratio percentage by cross-sectional area as defined in the National Electrical Code (NEC). The NEC specifies the fill ratio to ensure that the cables do not get overcrowded within the conduit, which can lead to increased heat buildup, cable damage, and reduced performance over time. It's crucial to refer to the latest NEC guidelines to get the accurate maximum percentage for the fill ratio.
Optical fiber installations come with unique considerations compared to traditional copper cabling, including attention to the numerical aperture which relates to the acceptance of light rays into the fiber. The numerical aperture can be determined by using the angle a max as figure 26.18 suggests, which pertains to the light-carrying capability of an optical fiber. Though related, this is independent of the conduit fill ratio, which is more about physical space rather than the optical properties of the fiber..