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When using any fiber optic test equipment, it is assumed that the user is familiar with the basics of fiber optics testing, including link
configuration and test procedures (such as “zeroing” and link budgets).
While Fiber OWL 7 BIDI fiber certifiers are able to test any fiber link configuration, the test procedures described in this section
assume that the fiber link was properly designed, installed, and tested according to industry standard requirements and
recommended “best practices”.
NETWORK DESIGN.
Both ends of an installed fiber link should terminate at an interconnection, such as patch panels in telecom
closets or wall outlets in work areas.
Interconnections provide an external connection point for any attached equipment -- whether it be active equipment or test
equipment -- for the purpose of protecting fragile installed fiber from direct handling.
REFERENCE METHOD.
The preferred reference method is the 1-JUMPER REFERENCE METHOD as defined in TIA/EIA-526-7
(singlemode) and TIA/EIA-526-14 (multimode). This method is called “1-jumper” because only one test jumper is connected between
the test equipment light source port and power meter port during the process called “setting a reference” (a.k.a. “zeroing”).
To most technicians, it seems logical to connect two test jumpers together with an adapter -- one for the power meter and one
for the light source -- to set a reference. However, this extra adapter introduces significant uncertainty into the reference power,
resulting in a less accurate final insertion loss measurement.
Eliminating the second test cable and adapter with the 1-jumper method reduces uncertainty. While the loss of the second cable
does become part of the loss measurement, the technician will check the second cable prior to actual testing to ensure it introduces
only a small amount of loss. Doing so will improve the overall accuracy of the final insertion loss measurement.
NOTE:
for non-standard link configurations, such as a patch panel on one end, or “home run” (i.e. no patch panels), technicians
may need to adjust their test procedure and reference method accordingly.
TEST PROCEDURES
BEFORE YOU BEGIN
