6 TRUNK INSTALLATION
CONSIDERATIONS WITH ARMORED, OUTSIDE PLANT AND HIGH FIBER COUINT CABLE
CONSTRUCTION
At the point of termination, fibers can be 900μm tight buffered, 250μm bare or loose tube or
250μm ribbonized. Depending on the outer jacket construction and fiber count, cables often need
to exit the outer sheath or jacket and be presented to the HDF Frame at a sub-unitized level.
Factors include:
• Outer Jacket or sheath construction (OSP, Foiled, Armored, Air Blown).
• Outside diameter of trunk cable or sub-unitized tubes and bend radius limitations.
• Fiber count and sub-unitized configuration of bulk cable.
• Maximum cable/tube diameter a splicing device can accept.
• Maximum number of fibers each cable management device can support.
The goal in most fiber optic installations is to maintain the protective qualities within the cable's
construction up to the point of termination. Attention needs to be made to allow for proper routing,
bend radius control and exposure of fibers to successfully perform a fusion splice.
Minimum lengths for expose sub-units in Leviton products:
Leviton recommends a minimum of the following lengths required to perform terminations in
Leviton SDX or HDX splicing products. Each termination scenario should be evaluated prior to
cable preparation. Each measurement is from the exit point of the bulk fiber cable jacket to the
end of the exposed sub-unitized tubing containing the individual fiber strands.
• HDX Frame – minimum of 50 inches/127 cm (from exit of trunk clamp)
This length does not factor in the following:
• Removal of additional length prior to beginning the termination process to eliminate any
damage or stress associated with handling of the end of the cable during the pulling process.
• Required or desired overall slack storage (see references in this document)
29