Fiber Optic Testing
When you finish this Fiber U Course, you may take an online exam for your Fiber U Certificate of Completion.
Objectives: From this self-study program you should learn:
- What needs testing in fiber optics? - components, cable plants, networks
- What equipment is needed to perform the tests
- How are these tests performed?
- What options exists for making the tests?
- How are the tests affected by network types (telco, long haul, LAN, FTTx, etc.)?
- How to calculate loss budgets to compare to test results
- When testing loss, what is the expected value?
- How accurate are the tests? How can they be made more accurate?
- What documentation should be kept on the tests?
- How is troubleshooting done?
- How does one write a test plan as part of a SOW (scope of work)?
- What are common mistakes made in testing?
- What standards apply to testing and how to use them?
This self-study course may be used as preparation for the CFOS/T Certification Exam
Definition: metrology: noun, the scientific study of measurement. ORIGIN early 19th cent.: from Greek metron ‘measure’ + -logy.
It should come as no surprise that there is a science for measurements. That science, called metrology, is dedicated to ensuring that measurements are made in the proper method and that the uncertainty of the measurement is known. Therefore, since we will treat fiber optic testing as a serious scientific topic, we could justify calling this self-study program a "metrology program." But don't assume it's too difficult; the purpose of this self-study program is to help the student understand "the science" of fiber optic testing, it's purposes, methods and limitations. We're just going to skip the hype and myths and focus on the real world.
Why is fiber optic testing important? Most of the technical questions we get at FOA are about testing problems. Sometimes it is about how to test, but more often it's about some test that has already been done but the answer is confusing. Not understanding testing or how to interpret the results of testing can be extremely expensive. We have seen perfectly good cable plants ripped out because they were tested improperly or test results misinterpreted. We have seen installers have to retest entire systems at their own expense because they tested improperly.
Perhaps the single most common cause of testing problems is lack of understanding of how to properly use test instruments and accessories. With this Fiber U self-study program we will try to make fiber optic testing simpler to understand by breaking the testing process into six steps, the same steps we use in our FOA standards:
1. What needs to be tested?
2. What equipment is needed to perform the tests?
3. What are the procedures for making the test?
4. What are the options required to implement the tests under various conditions?
5. What are the sources of error in the measurements?
6. What documentation is required for the tests?
The order of these steps is important, since it is the sequence of how one solves the problem of testing performance values for the component, subsystem or system and establishes the validity and precision of the measurement. Once one describes the test methodology itself, it is appropriate to describe the contributions to the uncertainty of the measurement (potential errors) and ways to reduce that uncertainty. Of course, after the test is completed, documentation is needed to validate the record of the tests.
There is a lot of material to cover here, so let's get started
Directions for taking this Fiber U self-study course:
It is assumed that the student has a basic knowledge of fiber optics at least at the basic CFOT or CPCT level. Review of basic fiber optics can be done on the Fiber U website with either the Basic Fiber Optics, Premises Cabling or OSP Fiber Optics self-study courses or by viewing videos on the FOA YouTube channel "thefoainc."
Students will be instructed to read the references, watch videos and take the quizzes (Test Your Knowledge) to complete the "classroom" part of the course. Several case studies are included where students will be quizzed on their troubleshooting skills.
Get a "Fiber U Certificate of Completion" When You Complete The Course
After you complete the Fiber U Fiber Optic Testing online self-study course, you can now take an online exam and, when you pass the exam, get a "Certificate of Completion" for this course. You should complete all lessons including taking the quiz ("Test Your Comprehension") at the end of every lesson. When you think you are prepared, you can take an online exam for a nominal fee ($20) which will give you a "Certificate of Completion" for this course.
If you are working on FOA certification, print out (PDF) your completed case studies from Lesson 8 and save along with your Fiber U Certificate of Completion for your application for certification.
How To Get Your Certificate of Completion For This Course
When you finish all lessons, go here to take the Fiber U Fiber Optic Testing Certificate of Completion Exam
Please note: receiving this Fiber U Certificate of Completion does not include FOA certification or membership but it does become documentation of your knowledge of fiber optics and should be part of your portfolio of documented knowledge, other training and work experience that can qualify you to apply for FOA direct CFOT certification through the FOA "Work to Cert" program.
More details on getting a Fiber U Certificate of Completion are on the last lesson. Read more about the Fiber U Certificate of Completion program.
For more information on the FOA and its certification programs, go to the FOA page on certification.
For information on the FOA "Work to Cert" direct certification program for those with industry experience, go here.
FOA offers a specialist certification in testing (CFOS/T) that is available to any CFOT or CPCT. Many FOA schools teach CFOS/T courses. Current FOA members with appropriate industry experience may apply to take the online course for credit toward their requirements for the CFOS/T certification and apply for the certification exam. Contact the FOA for more details and an application.
Online FOA Reference
FOA Reference Guide to Fiber Optics( general), Basics/Testing, Test Section
FOA Reference Guide to Outside Plant Fiber Optics( general), Basics/Testing
FOA Reference Guide to Fiber Optics, Chapter 8
FOA Reference Guide to Outside Plant Fiber Optics, Chapter 8
FOA YouTube Videos, with individual links as appropriate
You may, if you wish, watch the entire video and then watch the referenced sections for a second time for greater comprehension.
Extra Credit Reading
Assignments beyond the basics required for the course will be listed as extra credit.
Use The Quizzes To Learn
At the end of each lesson there is a quiz in the section "Test Your Knowledge." The quiz asks questions about the material you have just studied. When you answer all the questions in the quiz, click on the button "Check Your Work" and it will grade the exam, give you correct answers on questions you miss and give you an explanation of why the answer is correct.
You can take the Testing Lab lessons in the Fiber U Basic Skills Lab to use what you learn here to make actual measurements. The Basic Skills Lab requires you have the proper equipment and gives directions on how to use all the instruments needed to make the basic fiber optic tests.
Lesson Plan No. 1: Overview of fiber optic testing
Lesson Plan No. 2, Fiber optic test parameters and instruments
Lesson Plan No. 3, Visual inspection, tracing and fault location
Lesson Plan No. 4, Testing the cable plant, insertion loss testing
Lesson Plan No. 5, OTDR Testing
Lesson Plan No. 6, Testing for components, networks and troubleshooting
This information is provided by The Fiber Optic Association, Inc. as a benefit to those interested in teaching, designing, manufacturing, selling, installing or using fiber optic communications systems or networks. It is intended to be used as an overview and/or basic guidelines and in no way should be considered to be complete or comprehensive. These guidelines are strictly the opinion of the FOA and the reader is expected to use them as a basis for learning, as a reference and for creating their own documentation, project specifications, etc. Those working with fiber optics in the classroom, laboratory or field should follow all safety rules carefully. The FOA assumes no liability for the use of any of this material.