Fiber Jumpers Inspection And Cleaning Methods

Optical patch cords used as jumper cables, also called fiber optic jumpers, are often used between the optical transceiver and fiber terminal box. The main purpose of fiber optic jumpers detection is to ensure the quality of system connection, reduce the failure factors, and identify the fiber point of failure in the event of a failure. There are many detection methods which are mainly divided into artificial simple measurement and precision instruments measurement.

• Artificial Simple Measurement: This method is generally used to rapidly detect the fiber jumpers' ON/OFF and distinguish fiber jumpers in construction. It uses a simple light source to infiltrate visible light into the fiber optic jumper from one end, and observe which one glows from the other side to achieve the detection. Although this method is simple, it can not quantitatively measure the attenuation and breakpoint of fiber optic jumpers.

• Precision Instruments Measurement: Using the optical power meter or optical time domain reflectometer (OTDR) to quantitatively measure the fiber jumpers, the attenuation of fiber jumpers andconnectors can be measured, even the breakpoint position of fiber optic jumpers can be measured. This method can be used to quantitatively analyze the reasons of fiber optic networks' failure and evaluate optical networking products.

Fiber optic jumper is mainly used in the engine room to realize the connections between the fiber terminal and the devices, the equipment and devices, and the ports of wiring closet. It is very commonly used in fiber optic networks. We found that in network maintenance, to make a good connection between fiber optic jumpers and fiber couplers (adapters), the fiber jumpers end face's cleanliness is an important factor, which directly affects the quality of network communications.

Fiber Jumper end face means the distal section of its two connectors. It is often an easily overlooked place, because of nonstandard operation, which can easily be contaminated. In the daily operation and maintenance to the light path, operating specifications should be strictly enforced to ensure the cleanliness of fiber jumpers face. If the fiber end face is polluted, we must follow standardized procedures for cleaning. Here are how to inspect fiber end face's cleanliness and the clean-up methods.

• Visual Inspection: Under normal circumstances the most common practice is to check the face dirt: Disconnect the device pick up the fiber jumpers against the light, by observing the side facing the bright light refraction to detect whether the end is clean and smooth. Through observation, if the end face of a smooth bright light reflection is considered relatively clean, if the side face of the light is reflected light and not too smooth, it is likely there is dirt or scratches end face of such face will seriously affect the quality of the optical transmission. Of course, with the end surface inspection apparatus can be more fully understand the details of the end surface.

• Instrument Checks: Currently fiber end face inspection tools for instrument more, which optical fiber microscope is the most widely used professional inspection equipment. Under normal circumstances for multimode fiber-optic microscope display magnification of 200 times, while for single-mode fiber-optic microscope display magnification of 400 times. More advanced fiber-optic microscope magnification can not only switch between the two, but also through the LCD screen displays the fiber end, and thereby not disconnect the device detects the fiber end, but also to avoid the risk of eye injury by laser.

Cleaning Methods
In the fiber jumper end face inspection process, once the optical fiber end surface microscopy revealed the presence of fiber dirt, it must be properly cleaned to avoid triggering a decline in the quality of the communication problems. Each method has its own maintenance staff to do cleaning and maintenance, different cleaning methods to get different cleaning effect, if conditions permit, or the help of professional cleaning tools to help better. The importance of clean face a lot of companies now have noticed, and develop a variety of face cleaning tools, the author will introduce the following tools to assist in a professional and non-professional tools assisted two end cleaning methods.

In the absence of tools to assist in the case need to prepare ethanol, clean cotton balls, lens paper. Cleaning procedure is as follows.

• 1) Clean cotton ball in one hand, and then ethanol drops on cotton balls, alcohol should not drop too much.
• 2) With an anhydrous alcohol with a cotton wipe face along the same direction, the number of dirt under the end of the product.
• 3) Put a good face with an alcohol wipe three or more layers of the folded lens paper to wipe face in the same direction until the alcohol is completely dry and the end face of the light reflection of bright reflective so far.
• 4) Carefully examine each end to reflect the circumstances and phototabdus whether the fiber end face of residual debris and, if necessary, repeat the above steps 1-3 until the end clean flawless so far.

In the cleaning process should use the right cleaning tools and cleaning steps if incorrect cleaning methods not only face clean ineffective, but also may cause permanent damage to the face. After cleaning, be sure to check again and then insert the connector end to ensure that contaminants have been completely removed. If necessary, you will need to be cleaned again again, in order to ensure complete removal of the first failed to clear the dirt, so that the end to keep clean.

The above talking about fiber jumpers end face inspection and cleaning methods are simple and feasible, but in the usual course of operation and maintenance we should enhance the awareness of this aspect's cleaning. Because dust and oil will damage the fiber coupling, when the fiber jumpers are not in use, we must use protective sleeve to protecte the fiber optic connector, as well as to fiber couplers. Every time before the use of fiber jumpers we should clean the end face using a fiber paper. With cleaning consciousness, we can effectively reduce the fiber jumpers failures, and improve the quality of fiber optic lines and maintenance efficiency.

How To Use Magnifier Inspect Fiber Optic Connector

We can use magnifier to check the fiber optic connector pin end, which quickly determined that the connector insertion loss is high or low, the need for re-grinding. With this method, you only need a few seconds, you can initially conclude that the connector meets the quality requirements. Than the use of instruments that measure the specific optical connector insertion loss value, and then determine wheter the quality meets the requirements, greatly reducing the time and improve efficiency.
Testing Equipment
Using fiber magnifier to check fiber optic connector pins end, we need at least the following equipment:
1. 200 times or 400 times of fiber optic magnifier(according to the type of fiber connector to check the selection of suitable fiber adaptor);
2. Pure alcohole and lens paper (hairless soft paper);
3. Light source (we used here instead of incandescent bulbs);
Testing Steps
Check the following steps:
1. Remove the dust cap at the end of the connector to check;
2. Insert the connector in the magnifying glass of the adapter;
3. If you can not see the field of vision magnifier pin end, then adjust the position of magnifier adjustment knob until the pin end graphics all entered the field of vision;
4. Adjust the focal length of the magnifying glass to the right position, making the pin end graphics to clear;
5. Check the pin end, works well for grinding connector. Its face should be round, very smooth, the end of the fiber core is flush with the pin, and showed concentric ring shape; If there is dust (or defects), use lens paper (hairless soft paper) stick of pure alcohol wipe until the surface no dust (or you can see the clear flaws);
6. The other end of the connector to remove the dust cap, and make the end of the pins on the incandescent bulbs, we just checked in the connector end can see the light, otherwise the connector where a fiber optic cable has broken;
7. Repeat the above steps, check again, you will see a very bright core pin end view may find minor flaws;
8. Exchange ends of the connector, repeat the above steps to check the other end;
9. Mark the connector end of the existing problems with the tag, using appropriate methods, or grinding or re-assembled connector, and then repeat the steps above to be checked.
Analysis of test results
The use of a magnifier fiber optic connector for the inspection, we can see that a very good grinding effect fiber connector pin end face should have graphical features, it can have a variety of different types of defects that the end face of the connector graphical features. According to what we see different kinds of graphics, combined with our analysis, we can take the appropriate measures for improvement, in order to ensure the quality of the connector.
Recommended to use at least 200 times (preferably 400 times) of the optical magnifier to be checked. In order to check the accuracy, certainly with and without the use of incandescent bulbs in both cases with a magnifier to check connector end. In both cases the control of the end face of the pattern that can better determine whether defective.
For a good grinding effect connectors, we do not need any additional processing, instrumentatioin can be used directly for subsequent testing. If the connector is more obvious defects (based on experience needed to judge), its loss is likely higher, beyond the acceptable range of technical requipments, we can directly determine the quality problems. But for smaller connectors defective, the loss may be within the required range, then we need to use instrumentation to determine the actual test.
How to determine whether the effect of the connector polishing is “Good”?
If the connector pin end and core are round, smooth, while the fiber core is flush with the pin end, concentricity good, it is “good”, and without blemish.
If one connector looks “bad”, then the center or not circular, or is not smooth, or concentricity deviation is large, or the presence of other defects. For example, if the fiber has partially broken, then its will not be a full circle core.
The most serious situation is that we are under a magnifier to see the clear outline of the core of the phenomenon we call “fragmentation”. More than a brief introduction to how to determine a connector is a “good” or “bad”.