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The Checkup: Putting Your Fiber Optic Network to the Test

The sharp increase in demand for more bandwidth, along with demand for the fastest transmission medium possible, has stressed the importance of reliable fiber optic test and measurement methods.

Photo of Reference Grade Fiber Optic Cable

Since fiber optic cable performance is so important, any disruption could cause an entire system to collapse. This scenario is a major risk, not only for fiber optic providers but also consumers and clients. Fiber optic network designers should take the extra step required to conduct fiber optic tests and measurements to determine if a network will work for the planned application.  

Every fiber optic cable should be tested for end-to-end insertion loss, continuity, and polarity, before troubleshooting any problems. It is important to note that there are different fiber optic test and measurement methods for different kinds of fiber optic networks. For example, if you have a longer network that stretches hundreds of kilometers with intermittent splices, you’ll likely need to verify the individual splices with an Optical Time Domain Reflectometer (OTDR) tester. If your network has a limited range, you may consider a power meter and light source tester.

Visual Tracing for Fiber Optic Test and Measurement 

Fiber optic networks rely on infrared light to operatewhich is invisible to the naked eye. However, continuity tracing within the fiber glass using a LED light source – which is visible – can determine if fiber is broken.  

This fiber optic test and measurement method is fairly straightforwardAttach a visual fault locator and look at the other end of the fiber to see the light transmitted through the core of the fiber. If there is no light at the end, examine the different connections to find the broken fiber. 

Power Meter and Light Source  

Another reliable fiber optic test and measurement method uses a power meter and light source. Also known as a one-jumper or single-jumper method, this test is an accurate way to measure any signal loss that occurs within your fiber optic network.  

To perform this test, you’ll need a specialized light source and a power meter. Disconnect all active fiber cords, then calibrate the testing equipment.  

Begin by verifying the proper wavelength. From there, use the jumper cables and connectors that come with the testing equipment. Attach the jumper cable to the equipment and switch off the power meter before firing. Take note of the power reading.  

After that, use an adapter to connect a test reference cord for the test. This must be placed between the test equipment and the jumper cable. Attach both fiber optic cables to the source and the meterBe sure to disconnect the cables from the adapter. Place one of the jumpers at the end of the fiber cable to test, and the other jumper at the opposite end. If your cables are working properly, the values should be within the same range.


Photo of Singlemode OTDR Fiber Launch BoxTroubleshooting with an OTDR Tester 

An optical time domain reflectometer is a fiber optic tester used to troubleshoot fiber optic networks. The purpose of this fiber optic test and measurement method is to detect, locate, and measure disruptions at any location on a fiber cable.  

One of the main benefits of an OTDR is that it operates as a one-dimensional radar system, allowing for complete fiber test and measurement from the test-only end of the fiber network. The OTDR generates geographic information regarding localized loss and reflective events, providing fiber optic technicians with a pictorial record of the fiber cable’s characteristics, which may affect the fiber optic network’s performance.


Megladon Manufacturing in Austin, Texas is a company steeped in a diverse, rich, and technologically-savvy history. We anticipate that fiber optic connectivity demands will only increase. For over 20 years, Megladon has provided fiber solutions with a complete product portfolio including cable and test and measurement equipment. These products are available for purchase online at    

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About Megladon

A global industry leader in fiber optics and your premier partner for fiber optic connectivity, Megladon has spent over a decade developing fiber optic technology and perfecting the HLC interconnect. Our patented technology and process results in a reference grade interconnect that is reliable, rugged, repeatable and provides maximum performance. With millions of our products deployed worldwide, our fiber optic technology has been proven time and again to solve many of the problems encountered in network deployment and maintenance. We have also been able to use HLC as the foundation piece to develop unique and passive fiber optic solutions for our customers.