HP 86060C Series, User Manual

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General Information
Care of Fiber-Optic Connectors
scrape material off the inside of the connector or even break the inside sleeve
of connectors made with ceramic material.
• Avoid over tightening connections.
Unlike common electrical connections, tighter is not better. The purpose of
the connector is to bring the endfaces of two fibers together. Once they touch,
tightening only causes a greater force to be applied to the delicate endfaces.
With some connectors, the end can set itself off-axis with a tight connection,
due to the curved face, resulting in misalignment and excessive return loss.
Many measurements are actually improved by backing off the connector pres-
sure. Also, if a piece of grit does happen to get by the cleaning procedure, the
tighter connection is more likely to damage the glass. Tighten the connectors
just until the two fibers touch.
• Keep connections covered when not in use.
• Use fusion splices on the more permanent critical nodes. Choose the best con-
nector possible. Replace connecting cables regularly. Frequently measure the
return loss of the connector to check for degradation, and clean
every connec-
tor, every time.
All connectors should be treated like the high-quality lens of a good camera.
The weak link in instrument and system reliability is often the inappropriate
use and care of the connector. Because current connectors are so easy to use,
there tends to be reduced vigilance in connector care and cleaning. It takes
only one missed cleaning for a piece of grit to permanently damage the glass
and ruin the connector.
Visual inspection of fiber ends
Visual inspection of fiber ends can be helpful. Contamination or imperfections
on the cable end can be detected, as well as cracks or chips in the fiber itself.
Use a microscope with 100× to 200× magnification to inspect the entire end
face for contamination, raised metal, or dents in the metal as well as any other
imperfections. Inspect the fiber for cracks and chips. Visible imperfections not
touching the fiber core may not affect performance, unless the imperfections
keep the fibers from contacting.