Fiber Handling Guidelines - Moog Focal 903 User Manual

903-0628-00 Rev. 1
5.3

Fiber Handling Guidelines

1. Observe the bend radius of fiber optic cables at all times
When mounting, disassembling, or reassembling the cards, ensure that no fibers are subjected to bends
in excess of those held by the natural routing of the fibers. The minimum bend radius of the fibers should
generally be no less than 25 mm, though single loops may be less than this – as low as 15 mm – without
damaging the fibers. Keep in mind that allowable values are dependent on the type of fiber and the
environment, and cable manufacturers typically specify the minimum bend radius. Avoid even temporary
bends with a radius less than 25 mm, which may induce cracks that affect long-term reliability of the
fibers.
Momentary violations of bend radius or excessive lateral pressure may significantly reduce the long term
reliability of fiber, even if it appears undamaged. When in doubt, do not use the fiber.
2. Ensure fiber optic components are of the same type
All jumpers, cables, connectors, couplers, and Fiber Optic Rotary Joints (FORJs) used in the external
optical system connecting the remote to console fiber multiplexer board (FMB) must use the same type of
fiber. All components in the fiber link should be singlemode, typically Corning SMF 28 (9/125 µm)
or equivalent. A single mismatched jumper in the system may cause intermittent or persistent optical link
errors. Do not rely on cable jacket or connector colors alone to determine the type of optical fiber.
3. Use clean connectors
It is critical to ensure all fiber connectors are clean and free of dirt and debris. Even a small amount of
dirt or fluid contaminant may degrade link performance, and most reported optical link problems are due
simply to poor or contaminated optical connections.
 Keep protective dust covers on bushings, turrets and fiber connectors when not in use.
 Do not touch the white ceramic ferrules of the connectors with bare hands or objects, other than
cleaning materials.
 Prior to making a fiber connection, clean the barrel and tip of the ferrule using a suitable solvent, such
as reagent grade isopropyl alcohol, and a lint free optics cleaning tissue, such as Kimwipes
Carefully dab any dirt or debris off the face of the ceramic ferrules. Excessive dirt may need to be
cleared with pressurized air from a can prior to wiping the ferrule to avoid scratching the fiber itself.
Do not used air from a compressor as it may be contaminated with oil.
 During mating or unmating of fiber connectors with bushings, keep the connector aligned as straight
as possible. Avoid side loading the ceramic ferrule, which can crack the internal alignment sleeve in
the bushing.
 Ideally each fiber connector should be inspected with a handheld fiber microscope prior to final
assembly to ensure there are no scratches, pits, debris, or fluid contamination on the fiber face.
Focal Technologies Corp.
NEVER look into the end of a fiber when it is plugged
into a transceiver or active fiber, especially when
using a magnifying instrument, such as a fiber
microscope.
Model 903-HD User's Guide – FMB-X-2.5
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EX-L.
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