Plastic Optical Fiber Cable Assembly Testing
To ensure the quality of cable assemblies and other fiber optic components, several tests have been developed and standardized by the Fiber Optics Association. This gives engineers, manufacturers, technicians, and installers a baseline to work towards.
The following sections give an overview of common fiber optic cable testing techniques.
Single-ended cable assembly testing: FOTP-171
FOTP-171 is a test that was developed for testing connectorized POF cable, designed with repeatability in mind. It involves using a launch reference cable with a known insertion loss to connect a power source to the cable under test, which is connected to a power meter. This allows for the insertion loss of the cable under test, plus the connectors mating it and the reference launch cable, to be measured.
Double-ended cable assembly testing: OFSTP-7/14
Similarly, it is possible to perform a double-ended test for cable assemblies, which measures the combined loss of the connectors on both ends and the fiber itself. Between one and three reference cables are used for this test, for launch (from the power source) and receive (to the power meter), with the cable under test is connected between them.
- One reference cable (launch) required: Test equipment matches cable under test’s connectors
- Two reference cables (launch and receive) required: Test equipment does not match connectors
- Three reference cables (launch, receive, and “golden” reference cable) required: Test equipment does not match connectors and one reference cable must be converted male/female
Cable Substitution Test
In cases where connectors do not match test equipment, a cable’s insertion loss can be measured using comparing a reference cable with the same connectors. The cable under test’s insertion loss is measured, and subtracted from the reference cable’s insertion loss. For some applications, this comparative test may be adequate for troubleshooting or ensuring a patch cable’s usability.
(2014) The FOA Reference For Fiber Optics – Testing Fiber Optic Patchcords And Cables [Online]. Available: http://www.thefoa.org/tech/ref/testing/test/FOTP-171.html.
(2014) The FOA Reference For Fiber Optics – Testing Installed Fiber Optic Cables [Online]. Available: http://www.thefoa.org/tech/ref/testing/test/OFSTP-14.html.