Problem Solving

When it comes to fiber installations, fiber contractors are front-liners and are the first respondents in dealing with troubleshooting of installation issues. Problems within a fiber connector can occur due to a wide variety of reasons, from contamination to macrobend. Because of this, even the most experienced installers will eventually encounter some challenges or problems during installation.

In this article, we will take a closer look at three common problems, their likely cause, and how to fix them.

Connector Cleanliness

Fiber is often installed in harsh environments, such as dirty cellars or muddy construction sites, hence dirt and contamination often becomes an issue that can severely degrade service performance. However, despite this fact, fiber contractors sometimes choose not to test completely due to time constraints, thus leading to faulty service connection due to poor-quality installations.

In fact, any contamination in the fiber connection can cause failure of the component or even the whole system. This is because fiber optic networks function by carrying pulses of light between transmitters and receivers. For the network to send data successfully, the light needs to arrive at the end of the cable with sufficient power. Dirt and contamination block the signal, which leads to blocked lights that reduces power and efficiency. A dust particle as small as 1 micrometer on a single-mode core may block up to 1% of the light, causing a 0.05dB loss. Other contaminants, such as oils from human hands or film residues from air vapor, are more difficult to remove than dust particles and may cause equipment damage if not removed. Furthermore, dirt can cause permanent damage to the end-face equipment. Failures in the network caused by dirt will increase the expenditure and on-site installation time, as installers need to track down and replace the equipment.

To fix this issue, completely removing the contaminants from fiber-optic connection is recommended. Always complete the steps in the cleaning procedures carefully to avoid any further damage. Best practice is to use high-grade, fully lint-free wipes and pure Isopropyl alcohol to clean the end face. The goal is to remove any dust or contaminants, thus providing a clean environment for the fiber-optic connection to function efficiently.

Macro and Microbending

Bending in fiber optics fall into two categories: macrobends, which refers to bends that are large enough to be seen by naked human eyes, and microbends which are microscopic deviations along the fiber axis. Macrobend loss refers to losses induced in bends around the corners of installations, which are generally more at the cable levels. It is commonly caused by tight installation or handling, and may cause high vulnerability around in-house cabling. Fortunately, macrobend can be located and detected using OTDR tools, such as the Viavi Solutions T-BERD MTS 6000. To learn more about VIAVI OTDR Testing Equipment, click here.

Meanwhile, microbend loss refers to small scale bending in the fiber that is often caused by manufacturing defects, mechanical constraints during the fiber laying process, and environmental variations, such as temperature, humidity, or pressure during the fiber’s lifetime. Typical causes of microbending include freezing water that are causing external pressure or sharp objects impeding the fiber’s lifetime. Using a Visual Fault Locator (VFL) could assist technicians to easily see any light escaping from bends or breaks in the fiber, which can be helpful to locate microbends.

Faulty and Broken Splitter

There are two types of problems that may occur with splitters. Firstly, faulty splitters that have good and bad legs may cause an increased loss to some customers, but not others. The second problem is a broken splitter, which results in disrupted service to all customers. In both situations, it is recommended to perform an OTDR Test to locate the issue and find the problematic splitter. Once found, replace the splitter and re-test to ensure that no other issues are present.

Always look for the right tools when it comes to fixing problems during installation, as it will help you to solve network problems quicker and thus saves more time. Choose long-lasting tools that are capable of standing up to the wear and tear of daily use, and are durable enough to handle extreme conditions. VIAVI offers professional fiber optic tools to help you with any fiber maintenance and troubleshooting jobs. Choose from a variety of expertly configured fiber test kits, containing all the tools that you need to quickly resolve the trouble on hand.