Tag Archives: fiber connector

A clear understanding of the difference between fiber pigtail and patch cord

Previously, I only know different in appearance of the fiber pigtail and patch cord.

The fiber optic patch cord = fiber optic connector + fiber optic cable + fiber optic connector

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but the fiber optic pigtail = fiber optic connector + fiber optic cable. I think like this is easy to separate between them.

12fibers SCUPC SM pigtail

Recently, I have readed a discussion about the difference between fiber pigtail and patch core. There are so many professinal people to discuss it. They give me a clear understanding that:

Patch cords are made from either single or multi-fiber cables (usually rated for indoor use) and connected at each end with fiber cable connectors (either single fiber or multiple-fiber connector). Sometimes patch cords are called jumpers, especially if they are simplex or duplex. The connectors are selected to mate with the interfacing equipment or cable connectors. The important idea is that the cable has a connector at each end. The fiber can be either tight or loose buffered and the cable can be made of various diameters (1.2 mm to 3.0 mm are common). The patch cord may have one type of connector (ST FC, SC, LC, etc) on one end and a different connector on the other as long as all the fibers are connectorized on each cable end – this is a transition jumper. Patch cords are commonly used to connect ports on fiber distribution frames (FDFs). The  new mpo connecter make it  possible to run a singel cable that automatically terminates 12 fibers in one easy plug in.  Compared to common patch cord with ST FC, SC, LC connetor, MPO cable is a truly innovative and amazing group of products that really takes fiber optics into the new millennium.

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A pigtail is a cable (like a pach cord or jumper) with only one end terminated with an optical connector. Patch cords are often cut into shorter lengths to make two pigtails. Pigtails are found anywhere, but more commonly in optical assemblages or optical components

Pigtails are installed where they will be protected and spliced,lets say on the inside of the ODF and that’s why they are normally not sheathed. They have a coating colour so that you slice them on the corresponding colour on the out coming fiber.
On the other hand patch codes are used between the ODF to the WDM MUX or equipment. If you cut a patch code for use as pigtail then in case of future faulting where you are dealing with multiple pairs it will be difficult. But still if you need to cut the patch code check on its characteristics.

In general, the only major physical differnce b/w patch cord & pigtail is that patch cord is a fixed length piece of cable with dual ended fiber connector type may vary & pigtail is one meter standard OFC core with white white colored jacket. As per standard pigtail can only be used for OFC termination purpose & patch cord is to be used to connect the active component with ODF so that means pigtail can not be used at the place of patch cord.

What Is Visual Fault Locator and How to Use It

The Fiber Fault Locator (VFL) is an essential tool for every Fiber Termination Kit. It is like the continuity tester. The VFL is not one of the least expensive tools in your tool kit. It will allow you to quickly identify breaks or macrobends in the optical fiber, and identify a poor fusion splice in multimode or single-mode optical fiber.

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The big difference between the VFL and the continuity tester is the light source and optical output power of the light source. The VFL typically uses a red (635-650nm) laser light source. The optical output power of the laser is typically 1mW or less. Because of the high optical output power, you should never view the output of the VFL directly.

The Visual Fault Locator is available in different shapes and sizes. Some may look like a pen. Others may be built into an optical time domain reflectometer (OTDR), and some may look like a small test equipment box. There are two types of VFLs: contact and non-contact. With a contact VFL, the optical fiber under test will make contact with the VFL. However, with a non-contact VFL the optical fiber under test will not touch the VFL.

Unlike the continuity tester, the VFL is not limited to testing multimode optical fibers 2km or less in length. The VFL can be used to verify continuity of multimode or single-mode optical fiber longer than 2km. Due to attenuation of the 635–650nm laser light source by the optical fiber, macrobends may not be detectable beyond 1km in multimode optical fiber and 500 meters in single-mode optical fiber. The same holds true for finding breaks in the optical fiber through the jacket of the fiber-optic cable.

How to Use Visual Fault Locator

As with the continuity tester, the first thing you will need to do is clean the connector endface and inspect it with a microscope. If the endface finish is acceptable, the VFL can be connected to a Optical Fiber Connectors should not be viewed directly during this testing.

The VFL fills the core of the optical fiber with light from the laser. The light from the laser escapes the optical fiber at a break or macrobend. The light escaping from the optical fiber will typically illuminate the buffer surrounding the optical fiber. Macrobends are not always visible through the jacket but are typically visible through the buffer. Breaks may be visible through the jacket of the fiber optic cable depending on jacket color, thickness, number of optical fibers in the cable, and amount of strength member.

The VFL and the fiber OTDR work hand in hand with each other when it comes to locating breaks in an optical fiber. The OTDR can provide the operator with the distance the break. The VFL allows the operator to see the break in the optical fiber.

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Fiber optic cables are not the only place where the optical fiber may break. The optical fiber may break inside the connector or connector ferrule. Unless the optical fiber is broken at the endface of the connector, it is not visible with a microscope.

Usually, students connect cables that look great when viewed with the microscope but fail continuity testing. When this happens, the hardest part is determining which connector contains the break in the optical fiber. Without a VFL in the classroom, students would have to cut the cable in half and use the continuity tester to identify the bad connection.

The VFL will often identify the bad termination or connector.  Looking at the photograph, you can see VFL illuminating the break in the optical fiber. The output of the VFL is so powerful that it penetrates the ceramic ferrule.

The visual fault locator can be used to test the continuity of an optical fiber in the same manner. The first step when using the continuity tester is to clean and visually inspect the endface of the connector before inserting it into the continuity tester. After the connector has been cleaned and inspected, you need to verify that the continuity tester is operating properly. Turn the continuity tester on and verify that it is emitting light.

The visual fault locator also can be used to locate a macrobend in an optical fiber. However, macrobends do not allow nearly as much light to penetrate the buffer and jacket as does as break in the optical fiber. Locating a macrobend with the VFL may require darkening the room.

Macrobends and high loss fusion splices appear the same on an OTDR trace. The VFL allows the identification of a high-loss fusion splice.

MSA to Boost 400Gbps Copper Network Cable and Optical Fiber Transceiver Market

Five leading global companies plan to come to an agreement of multiple sources (multi – source agreement, MSA) to create CDFP (400Gbps form – factor pluggable) industry alliance, defines fiber optic transceiver module/plug and mainboard electric mechanical dimension edge connector .

New CDFP MSA aims to regulate and encourage 400Gbps hot swap module’s  development and commercialization, this module integrates 16 transport channels to receive 16 channels, supports passive and active copper networks, as well as the active fiber optic module.

Brocade, senior technical personnel said: “we expect this high integration fiber optic transceiver module allows network equipment maker has high density and higher data throughput of 400Gbps system solutions, MSA group plans to develop specification details, to promote the industry using compatible high density products.

CDFP MSA vendors are interchangeable in terms of mechanical and electrical products, this project will set electrical interface, optical interface and mechanical interface, may include optical fiber connector and plug with cable plug, electrical connectors, guide rail, the front panel and the main PCB layout requirements. Moreover, MSA specification is expected to include thermal, electromagnetic and electrostatic discharge design.

Molex group product manager Scott Sommers, said: “through the establishment of the front panel, the hot swap of 16 channel 400Gbps module of multiple sources of compatible, the collaboration is committed to increasing customer choice and ensure interoperability and interchangeability, fundamentally promote the whole copper and fiber optic transceiver market more rapid development.”

For more information about copper network cable and optical fiber transceiver, please visit our website: www.fs.com.