Figure-5: Cleaning Methods for Fiber Optic Adapter

Small as it is, fiber optic adapter is still an important part of the whole optical system, which should and also deserves to be cleaned according to the appropriate cleaning procedures. There are two basic cleaning methods—dry cleaning and wet cleaning.

1. Dry Cleaning: First, insert a dry adapter cleaning stick (or fiber adapter sleeve brush) inside the adapter and pull out with twisting motion; cleaning inside surface of the alignment sleeve. After cleaning the adapter with the connector installed on one end, inspect the connector end face for contamination.

2. Wet Cleaning: Insert an adapter cleaning stick (or fiber adapter sleeve brush) moistened with fiber optic cleaning solution (or > 91% Isopropyl Alcohol) inside the adapter and pull out with twisting motion; cleaning inside surface of the alignment sleeves. Follow up with a dry swab. After cleaning the adapter with the connector installed on one end, inspect the connector end face for contamination.

Electrodes are the most essential consumable of fusion splicing machine. In general, after a period of use, it needs to be replaced. This is the basic maintenance of fusion splicing machine. Thus, users of fusion splicing machines should have the ability to judge when to replace electrodes and master the maintenance knowledge of replacing electrodes. This post will guide you how to judge when to replace the electrodes and explain the replacing steps by taking example of the latest Fujikura fusion splicing machine FSM-80S.

When to Replace Electrodes of Your Fusion Splicing Machine
What’s the best time to replace the electrodes of your fusion splicing machine, and how do you know when to replace it? Different users have different methods according to their working experiences. But the most basic method to judge when to replace the electrodes will be introduced here. Generally, there are two basic ways to judge whether the fusion splicing machine needs to be replaced its electrodes.

There is a function of a fusion splicing machine called arc discharge count. Electrodes should be replaced after reaching the manufactures recommended arc discharges. In general, the fusion splicing machine will alarm to remind users to replace the electrodes in that case. You should replace the electrodes of your fusion splicing machine when you see this alarm. Otherwise, splicing loss and quality will be effected.

Users can confirm whether the electrodes need to be replaced through some abnormal conditions during using. For example, if you find that your fusion splicing machine often prompt discharge not stable during the splicing, or discharge correction can not pass normally, or even the tip of the electrodes are oxidate severely and bald, you should replace the electrodes in those cases.

How to Replace Electrodes of Fusion Splicing Machine
Electrodes Replacing Steps
We can see the electrodes replacing steps in the following picture. It shows us the electrodes replacing steps of the Fujikura latest FSM-80S fusion splicing machine.

 

 

After replacing the electrodes, it’s necessary to stabilize the electrode and conduct discharge correction in order to make sure that the new electrodes perform well. These can usually be done through instructions of the fusion splicing machine. In addition, we should use the discharge correction feature to get the best discharge power of the machine in daily use.

 

Visual fault locator, also called VFL for short, is an essential tool that quickly and easily locates problem areas in fiber cables. It is regarded as a part of OTDR and it is cheap. By pinpointing the exact location of the fiber damage, such as breakpoint, bending or cracking, technicians can diagnose, troubleshoot, and fix the problem effciently.

This device is based on laser diode visible light source, when the light injected into the fiber, if fiber fracture, connector failure, bending over, poor weld quality failure by launching the light of the fiber to fiber fault visualization positioning.Visual Fault Locator launched a continuous wave (CW) or pulsed mode. The typical frequency of 1Hz or 2Hz, but can also work in the kHz range. Usually the output power of 0dBm (1mW) or less, the working distance of 2 to 5km, and to support all the common connector.

Visual fault locators generally include the pen type, handheld type and portable visual fiber fault locator. In addition, designed with a FC, SC, ST adapter, VFL is used without any other type of additional adapters, it can locates fault up to 10km in fiber cable, with compact in size, light in weight, red laser output.

The visual fault locator is commonly used for fiber identification and fault location of single-mode or multi-mode fiber as well as for wavelength loss testing. It is also an ideal tool for the examination of all types of patch cords and ribbon or bunched pigtails. It is an excellent tool for the maintenance of fiber optic networks, optical systems including LAN, FDDI and ATM, telecommunications and CATV networks. It is intended for the identification,fault location of fiber optics on single mode or multimode fiber and wavelength loss testing. It can also locate the fault of OTDR dead zone and make fiber identification from one end to the other end.

While both types perform the functions above, the difference between the two categories of cleavers is the percentage yield of good cleaves. An experienced fiber optic technician will achieve approximately 90% good cleaves with a scribe cleaver, while the precision cleaver will produce 99% good cleaves. The difference doesn’t seem like much so you may hardly to make a specific decision. My suggestion is to buy precision cleavers if you plan to use a lot of mechanical splices or pre-polished splice/connectors. It will pay for itself in no time. If you decide to use the inexpensive scribe cleavers, you must learn how to use it properly. Follow directions, but also do what comes naturally to you when using the device, as they are sensitive to individual technique. Inspect the fibers you cleave to see how good they are and keep practicing until you can make consistently good cleaves.

Precision cleavers are the most commonly used cleavers in the industry. They use a diamond or tungsten wheel/blade to provide the nick in the fiber. Tension is then applied to the fiber to create the cleaved end face. The advantage to these cleavers is that they can produce repeatable results through thousands of cleaves by simply just rotating the wheel/blade accordingly. Although more costly than scribe cleavers, precision cleavers can cut multiple fibers while increasing speed, efficiency, and accuracy. In the past, many cleavers were scribes, but over time, as fusion splicers became available and a good cleave is the key to low splice loss, precision cleavers were developed to support various applications and multiple fiber cleaving with blades that have a much longer life span.

A traditional cleaving method, typically used to remove excess fiber from the end of a connector before polishing, uses a simple hand tool called a scribe. Scribe cleavers are usually shaped like ballpoint pens with diamond tipped wedges or come in the form of tile squares. The scribe has a hard, sharp tip, generally carbide or diamond, that is used to scratch the fiber manually. Then the operator pulls the fiber to break it. Since both the scribing and breaking process are under manual control, this method varies greatly in repeatability. Most field and lab technicians shy away from these cleavers as they are not accurate. However, if in skilled hands, this scribe cleaver offer significantly less investment for repairs, installation, and training classes.

We know that the closer to 90 degrees the cleave is, the more success you will have with matching it to another cleaved fiber to be spliced or mated by a connector. So it’s important to use the proper tool with good technique to consistently achieve a 90 degree flat end. Good cleavers are automatic and produce consistent results, irrespective of the operator. The user need only clamp the fiber into the cleaver and operate its controls. Some cleavers are less automated, making them more dependent on operator technique and therefore less predictable. There are two broad categories of fiber optic cleavers, scribe cleavers and precision cleavers.

A cleave in an optical fiber is a deliberate, controlled break, intended to create a perfectly flat end face, perpendicular to the longitudinal axis of the fiber. A fiber optic cleaver is a tool that holds the fiber under low tension, scores the surface at the proper location, then applies greater tension until the fiber breaks. Usually, after the fiber has been scored, the technician will use a cleaver either bend or pull the fiber end, stressing the fiber. This stress will cause the fiber to break at the score mark, leaving a 90 degree flat end if all goes well. So the cleaver doesn’t cut the fiber. In fact, it just breaks the fiber at a specific length.

To get good fiber optic splices or terminations, especially when using the pre-polished connectors with internal splices, it is extremely important to cleave the fiber properly. If the fiber ends are not precisely cleaved, the ends will not mate properly. To prepare a fiber end for a connector or splice, the end of the fiber must be cleaved to a 90 degree flat end. For technicians the problem is that the end of the fiber strand is so small that it is impossible to tell with the naked eye whether the strand has a flat end. So in order for this to happen, you must use a cleaving tool called fiber optic cleaver. Some knowledge of fiber optic cleaves will be provided in this article.