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What is The Fiber Identifier

The Fiber Identifier acts as the fiber optic installer or technician’s infrared eyes. By placing a slight macrobend in an optical fiber or fiber-optic cable, it can detect infrared light traveling through the optical fiber and determine the direction of light travel. Some fiber identifiers can also detect test pulses from an infrared (800–1700nm) light source.

The fiber identifier typically contains two photodiodes that are used to detect the infrared light. The photodiodes are mounted so that they will be on opposite ends of the macrobend of the optical fiber or fiber-optic cable being tested. The electronics in the fiber identifier measure the detected light energy and display the direction of light travel through the optical fiber.

The optical fiber identifier is used very much like the Fiber Locator (VFL) when it comes to troubleshooting. But there are two difference: One key difference is that the fiber identifier replaces your eyes. Another difference is that fiber optic cable under test typically does not have to be disconnected from an active circuit – it can remain plugged into the transmitter and receiver.The fiber identifier can typically be used with coated optical fiber, tight-buffered optical fiber, a single optical fiber cable, or a ribbon cable. Each of these must be placed in the center of the photodiodes during testing. Selecting the correct attachment for the optical fiber or optical-fiber cable type under test typically does this.

Figure 1 shows Fiber identifier optical fiber and fiber-optic cable attachments

The fiber identifier can also be used with external light source. Often the external light source is an Fiber OTDR. Many OTDR manufacturers build or program in a pulsed output function. When set for a pulsed output, the OTDR emits a continuous pulse train at a predetermined frequency. The electronics in the fiber identifier can detect preset frequencies and illuminate the corresponding LED. This feature can be very helpful when you are trying to identify an unmarked tight-buffered optical fiber within a bundle of tight-buffered optical fibers. This feature can also be helpful when you are trying to approximate the location of a break in the optical fiber.

The fiber identifier can be used with the OTDR to narrow down the location of a break in an optical fiber when a VFL is not available or when the light from the VFL is not visible through the jacket of the fiber optic cable. If the index of refraction is correct, the OTDR should provide an accurate distance to the fault. The OTDR measures the length of optical fiber to the fault, not the length of fiber optic cable. The cable length may be shorter than the optical fiber length.

Once you have found the approximate location of the fault with the OTDR, set the OTDR or infrared light source to pulse at a predetermined frequency. Clamp the fibr identifier on the faulted fiber optic cable several meters before the approximate location of the fault. Check the fiber identifier for the predetermined frequency. If the fiber identifier does not detect the predetermined frequency, move the fiber identifier several meters closer to the OTDR or infrared light source and recheck for the predetermined pulse. If you have choosen the correct fiber optic cable test to the fault of the distance with you, you should be testing a predetermined frequency. If you still don’t test frequency, carefully check everything, and test again. If you still do not detect the predetermined frequency, there may not be enough optical energy for the fiber identifier to function properly.

Figure 2 shows optical fiber identifier

If you are able to detect the predetermined frequency, move the fiber identifier down the fiber optic cable away from the OTDR or infrared light source in one meter increments. Continue to do this until the fiber identifier no longer detects the predetermined pulse. You now know within one meter where the break in the optical fiber is located. At this point, you may want to disconnect the OTDR or infrared light source and connect the visible fault locator. The visible fault locator may illuminate the exact location of the fault. If the visible fault locator does not illuminate and conditions permit, darken the area around the fault. This may allow you to see the illuminated fault.

Essential Fiber Tools To Your Tool Bag

Here’s a list of fiber optic tools are essential to your tool bag when performing network admin duties.

Network Cable Crimper

Cable crimp tool is a tool designed to crimp or connect a connector to the end of a cable. For example, network cables and phone cables are created using a Network Cable Crimping Tool to connect the RJ-45 and RJ-11 connectors to the end of the cable. It can bend, cut, strip and crimp insulated

Wiring in a snap. For cable and phone installation specialists, a handy crimp tool can cut and strip electrical wiring in a few seconds. Most crimpers will be able to terminate both RJ-45 (8P8C) and RJ-11 styles of modular plug and may also feature a built-in wire cutter. Some ratchet and some don’t. When shopping mind:

Thick steel construction which extends for the entire length of both handles;
Several pounds of pull between the handles; a weak spring makes for a flimsy feel;
The “teeth” should be mounted on a floating hinge to ensure that pressure is applied evenly across all pins when crimping;
Should not rattle when shaken.

Cable Stripper

The fiber Fiber Stripper plays an important role in fiber optic cable splicing process. While you can make due with a cable cutter like knife or the scissors, a cable jacket stripper reduces crimping time and leaves a nice clean cut with a lower likelihood of nicking the inner wires. Only with a properly strip of the fiber cable jacket can make an undamaged exposed fiber which is also a must for successful splicing of two optical fibers. What to look for when shopping:

Sharp blade;
Ability to spin easily around a cable with one finger.

Punch Down Tool

Punch Down Tool, also called punchdown tool or Krone punch down tool, is a small hand tool used by telecommunication and network technicians. Most punch down tools are of the impact type, consisting of a handle, an internal spring mechanism, and a removable slotted blade. Impact tools or punch down tools are used to terminate individual wires on patch panels or 110/66 blocks. What to look for:

Adjustable spring tension;
Should include at least a 110-type blade (needed for Cat 5 patch panels).

Fiber Cable Slitter

Among all the types of fiber optic tools, the Cable Slitter is an efficient and indispensable tool for fiber optic cable termination, it is usually designed allows jacket or shield slitting on non-fiber optic configurations as well. They are always using for splicing wire, cutting harness ties, insulation materials, medium gauge wires and electrical tape or stripping fiber cable jacket. There are round cable slitters, armored cable slitters, longitudinal cable slitters and more cable slitter kits available. What to look for when shopping:

Blade Rotates 90º for Mid-Span Cutting;
Adjustable Blade Depths.

Cable Tester

Network Cable Tester is always being used to test LAN Datacom and Telecom cables. Network Cable Line Tester can find all problems associated with testing such faults as opens, shorts, cable integrity and it also find cable length of individual cables or distance to a fault, and its powerful and user-friendly features enable network installers to accurately check pin configurations of various voice and data communication cables.

If you’ve ever shopped for a LAN Cable Tester, you know that there are various types available. The one piece of gear in your tool kit you should absolutely not scrimp on is the cable tester. What to look for when shopping:

A reputable brand name;
Detachable termination component for remote wire mapping;
Tone generation capability;
Link speed detection;
Power over Ethernet detection.

Suggestions for modifications or additions are welcome, you may be need other cost-effective tools. The fiber optic tools mentioned above all you can have a wide selection at FiberStore Technology, especially it provides large discounts for a large quantity.

Fiber Optic Cables For Harsh Environment Applications

Fiber based systems offer apparent advantages over electrical methods in large plants and factories where the harsh environment threatens data reliability and security. Unlike copper cable, fiber optic cabling is resistant to electromagnetic interference (EMI), making it an ideal option for harsh environments involving high voltages or machinery with variable frequency drives, is a safe alternative to traditional wiring.

As you know, fiber optic cable consists of three parts: the core, the cladding, and the coating. The core transmits the light and has a high refractive index. The cladding contains the light within the core because its lower refractive index causes all the light rays to reflect back into the core. This “total internal reflection” or “fiber-optic effect” is the technology’s underlying principle. The coating, usually an acrylate polymer, protects the core/cladding assembly.

Optical fiber is typically made from high-purity silica glass. Plastic fiber of varying configurations is also available. But the attenuation of light energy can approach one thousand times that of glass fiber. The length and integrity of the transmission path and the core/cladding arrangement affect the bandwidth, or the frequency range that the optical fiber transmits. Fiber bandwidth is expressed in megahertz-kilometers (MHz-km).

Depending on the application, the distance involved, and the location, several types of cable configurations and connector types are available. Optical fiber is fragile and must be protected, mostly from mechanical stresses such as bending, crushing, thermal effects, and pulling during installation.

Tight Tube And Loose Tube Cable

A tight-tube (or tight-buffer) design has a PVC coating, which tightly bonds to the fiber, limiting movement. This cable type can have strength members, which you pull through conduit and cable trays. This design, however, has low crush resistance and is susceptible to deformation due to thermal expansion; thus, it is recommended for indoor use only.

A loose-tube design gives a fiber free movement. Each component of the Loose Tube Cables (the sheath or outer coating, the strength member, and the buffer tubes that carry the fibers) has different thermal characteristics. By allowing the fibers and the components surrounding them free movement, deformation is avoided.

Loose-tube construction has much better crush resistance than tight tube because of the buffer-tube protection of the fibers. Loose-tube cables have a strength member, which is used as the pulling member for conduit installation. Loose-tube cables are usually filled with a gel, which surrounds the fibers and increases protection from water. This also improves crash resistance because of the gel’s cushioning effect. You mostly use this cable type for outdoor applications, but you can also use it in harsh industrial environments. A drawback to this type of cable is the difficulty in handling individual fibers. The fiber coating does not have to be as thick as in tight-tube construction; thus, attaching connectors is difficult.

Remember that tight-tube construction does not allow for free movement and provides low protection against mechanical stress. It does, however, have a thick coating for ease of handling. Loose-tube construction, on the other hand, allows free movement and provides a good degree of protection.

Breakout Cable

Breakout cables are a hybrid solution. In a breakout cable, each fiber is treated as a separate unit, complete with a sheath and strength member. This design eliminates the need for a breakout kit, because the sheath lets you attach connectors easily.

Breakout Cable Fiber let fiber subunits move freely, and they protect each fiber by virtue of their thicker coating/strength member arrangement. Each fiber subunit is configured as a tight tube. Breakout cables also come equipped with a separate strength member just like the loose-tube design.

FiberStore harsh environment Fiber Cables is designed and manufactured with specialized components which provide improved performance and protection against damage, breakage, and performance limiting conditions that often exist in harsh environment applications. FiberStore has the resources, expertise, and experience to design, develop, manufacture, install, and maintain a product ideally suited for your exact application.

The Developing Of Ethernet Technologies

The most mature and common of the network applications is Ethernet. Over the past 25 years, despite stiff competition from more modern network architectures, Ethernet has flourished. In the past 10 years alone, Ethernet has been updated to support speeds of 100Mbps, 1Gbps (about 1000Mbps) and 10Gbps; currently 40 and 100 Gigabit Ethernet are being standardized in the IEEE 802.3b committee. Forty and 100 Gigabit Ethernet will be deployed over optical fiber for 100 meters or greater, and research is progressing to make it available over UTP for distances up to 10 meters.
Ethernet has evolved to the point that it can be used on a number of different cabling systems.

10Mbps Ethernet Systems

>>10Base-5: “Standard Ethernet Cable”
The earliest version of Ethernet ran on a rigid coaxial cable that was called Standard Ethernet cable, but was more commonly referred to as thicknet. While thicknet was difficult to work with (because it was not very flexible and was hard to install and connect nodes to), it was reliable and had a usable cable length of 500 meters. 10Base-5 systems can still be found in older installations, typically used as backbone cable, but virtually no reason exists for you to install a new 10Base-5 system today.>>10Base-T Ethernet

10Base-T : 10Mbps Ethernet over unshielded twisted-pair cable. Maximum cable length (network device to network card) is 100 meters.10Base-T (the T stands for twisted pair) Ethernet is less common today and has been overtaken by 100Base-T. Even though 10Base-T uses only two pairs of a four-pair cable, all eight pins should be connected properly in anticipation of future upgrades or other network architectures.

>>10Base-F Ethernet

Specifications for using Ethernet over Optical Fiber Cables existed back in the early 1980s. Originally, fiber-optic cable was simply used to connect repeaters whose separation exceeded the distance limitations of thicknet cable. The original specification was called Fiber-Optic Inter-Repeater

Link (FOIRL), which described linking two repeaters together with fiber-optic cable up to 1,000 meters (3,280´) in length. The cost of fiber-optic repeaters and fiber-optic cabling dropped greatly during the 1980s,and connecting individual computers directly to the hub via fiber-optic cable became more common.Originally, the FOIRL specification was not designed with individual computers in mind,so the IEEE developed a series of fiber-optic media specifications. These specifications are collectively known as 10Base-F. It is uncommon to use optical fiber at these slow speeds today. For historical purposes, the individual specifications for (and methods for implementing) 10Base-F Ethernet include the following:

>>10Base-2 Ethernet

10Base-2 is still an excellent way to connect a small number of computers together in a small physical area such as a home office, classroom, or

lab. The 10Base-2 Ethernet uses thin coaxial (RG-58/U or RG-58 A/U) to connect computers together. This thin coaxial cable is also called thinnet.

100Mbps Ethernet Systems

The 100Mbps version of 802.3 Ethernet specifies a number of different methods of cabling a Fast Ethernet system, including 100Base-TX, 100Base-T4, and 100Base-FX.

>>100Base-TX Ethernet

The 100Base-TX specification uses physical-media specifications developed by ANSI that were originally defined for FDDI (ANSI specification X3T9.5) and adapted for twisted-pair cabling. The 100Base-TX requires Category 5e or better cabling but uses only two of the four pairs. The eight-position modular jack (RJ-45) uses the same pin numbers as 10Base-T Ethernet.

>>The 100Base-T4 specification was developed as part of the 100Base-T specification so that existing Category 3–compliant systems could also support Fast Ethernet. The designers accomplish 100Mbps throughput on Category 3 cabling by using all four pairs of wire; 100Base-T4 requires

a minimu.m of Category 3 cable. The requirement can ease the migration path to 100Mbps technology.

>>100Base-FX Ethernet

Like its 100Base-TX copper cousin, 100Base-FX uses a physical-media specification developed by ANSI for FDDI. The 100Base-FX specification was developed to allow 100Mbps Ethernet to be used over fiber-optic cable. Although the cabling plant is wired in a star topology, 100Base-FX is

a bus architecture.

Gigabit Ethernet (1000Mbps)

1000Mbps Ethernet was supported only on fiber-optic cable. The IEEE 802.3z specification included support for three physical-media options (PHYs), each designed to support different distances and types of communications:

>>1000Base-SX
Targeted to intra-building backbones and horizontal cabling applications such as to workstations and other network nodes, 1000Base-SX is designed to work with multimode fiber-optic cable at the 850nm wavelength.

>>1000Base-LX
Designed to support backbone-type cabling such as inter-building campus backbones, 1000Base-LX is for Single-mode Fiber-optic Cable at 1310nm, though multimode fiber can be used for short inter-building backbones and intra-building cabling applications.

>>1000Base-CX
Designed to support interconnection of equipment clusters, this specification uses 150 ohm STP cabling similar to IBM Type 1 cabling over distances no greater than 25 meters. When cabling for Gigabit Ethernet using fiber, you should follow the ANSI/TIA-568-C standards for 62.5/125 micron or 50/125 micron multimode fiber for horizontal cabling and 8.3/125 micron single-mode fiber for backbone cabling. See Table 6 of Annex D in ANSI/TIA-568-C.0.

>>1000Base-T

Gigabit Ethernet over Category 5 or better UTP cable where the installation has passed performance tests specified by ANSI/TIA/EIA-568-B. Maximum distance is 100 meters from equipment outlet to switch. The IEEE designed 1000Base-T with the intention of supporting Gigabit Ethernet to the desktop. One of the primary design goals was to support the existing base of Category 5 cabling.

10 Gigabit Ethernet (10,000Mbps)

The IEEE approved the first Gigabit Ethernet specification in June, 2002: IEEE 802.3ae. It defines a version of Ethernet with a nominal data rate of 10 Gbit/s. Over the years the following 802.3 standards relating to 10GbE have been published: 802.3ae-2002 (fiber -SR, -LR, -ER, and -LX4 physical-media-dependent devices[PMDs]), 802.3ak-2004 (-CX4 copper twin-ax InfiniBand type cable), 802.3an-2006 (10GBASE-T copper twisted pair), 802.3ap-2007 (copper backplane -KR and-KX4 PMDs), and 802.3aq-2006 (-LRM over legacy multimode fiber -LRM PMD with electronic dispersion compensation [EDC]). The 802.3ae-2002 and 802.3ak-2004 amendments were consolidated into the IEEE 802.3-2005 standard. IEEE 802.3-2005 and the other amendments have been consolidated into IEEE Standard 802.3-2008. In the premises environment, 10 Gigabit Ethernet is mostly used in data center storage servers,high-performance servers, and in some cases for intra-building backbones. It can be used for connection directly to the desktop.

>>10GBASE-SR (Short Range)

10GBASE-SR (short range) uses 850nm VCSEL lasers over multimode fibers. Low-bandwidth 62.5/125 micron (OM1) and 50/125 micron (OM2) multimode fiber support limited distances of 33–82 meters. To support 300 meters, the fiber-optics industry developed a higher bandwidth version of 50/125 micron fiber optimized for use at 850nm.

>>10GBASE-LR (Long Range)

10GBASE-LR (long range) uses 1310nm lasers to transmit over single-mode fiber up to 10 kilometers. Fabry-Pérot lasers are commonly used in 10GBASE-LR optical modules. Fabry-Pérot lasers are more expensive than 850nm VCSELs because they require the precision and tolerances to focus on very small single-mode core diameters (8.3 microns). 10GBASE-LR ports are typically used for long-distance communications.

>>10GBASE-LX4

10GBASE-LX4 uses coarse wavelength division multiplexing (WDM) to support 300 meters over standard, low-bandwidth 62.5/125 micron (OM1) and 50/125 micron (OM2) multimode fiber cabling. This is achieved through the use of four separate laser sources operating at 3.125Gbps in the range of 1300nm on unique wavelengths. This standard also supports 10 kilometers over single-mode fiber. 10GBASE-LX4 is used to support both standard multimode and single-mode fiber with a single Optical Transceivers. When used with standard multimode fiber, an expensive Mode Conditioning Patch Cord is needed. The mode conditioning patch cord is a short length of single-mode fiber that connects to the multimode in such a way as to move the beam away from the central defect in legacy multimode fiber. Because 10GBASE-LX4 uses four lasers, it is more expensive and larger in size than 10GBASE-LR. To decrease the footprint of 10GBASE-LX4, a new module,10GBASE-LRM, was standardized in 2006.

>>10GBASE-LRM

10GBASE-LRM (long reach multimode) supports distances up to 220 meters on standard, lowbandwidth 62.5/125 micron (OM1) and 50/125 micron (OM2) using a 1310nm laser. Expensive mode conditioning patch cord may also be needed over standard fibers. 10GBASE-LRM does not reach quite as far as the older 10GBASE-LX4 standard. However, it is hoped that 10GBASE-LRM modules will be lower cost and lower power consumption than 10GBASE-LX4 modules. (It will still be more expensive than 10GBASE-SR.)

>>10GBASE-T

10GBASE-T supports 10Gbps over Category 6A UTP or Category 7 shielded (per ISO/IEC 11801Ed. 2) twisted-pair cables over distances of 100 meters. Category 5e is supported to much lower distances due to its limited bandwidth. Special care needs to be taken in installing Category 6A cables in order to minimize alien cross-talk on signal performance.

40 and 100 Gigabit Ethernet

The IEEE 802.3ba committee is standardizing 40 and 100 Gigabit Ethernet. This will be deployed over OM3 50/125 multimode optical fiber for 100–200 meters, and research is progressing to make it available over UTP for distances up to 10 meters.This could be the speed point at which there is mass conversion of copper to fiber-based systems.

References: FIBERSTORE PRODUCTS INFO

What are the Advantages and Disadvantages of Fiber Optic Cabling

Fiber optic cabling consists of strands of purified glass, or even plastic, rods that conduct specific wavelengths of light, analogous to the electrons carried along a Copper Ethernet Cable. However, light traveling through glass or plastic is not susceptible to the same problems that metal conductors are; The electromagnetic radiation that results from current traveling through a wire is not present in optical conductors, and optical conductors can be made much smaller than metal ones. Today, we’ll talk about the advantages and disadvantages of fiber optic cable.

Advantages and Disadvantages of Fiber Optic Cable

Everything has its own advantages and disadvantages. Learning the advantages and disadvantages of fiber optic cable, we may know how to select one when buying the cables.

Advantages

There are four advantages of fiber optic cabling, these advantages explain why fiber is becoming the preferred network cabling medium for high bandwidth, long-distance applications:

1. Immunity to Electromagnetic Interference (EMI)

All copper cable network media sharing a common problem: they are susceptible to electromagnetic interference (EMI), fiber optic cabling is immune to crosstalk because optical fiber does not conduct electricity and uses light signals in a glass fiber, rather than electrical signals along a metallic conductor to transmit data. So it cannot produce a magnetic field and thus is immune to EMI.

2. Higher Possible Data Rates

Because light is immune to interference, can be modulated at very high frequencies, and travels almost instantaneously to its destination, much higher data rates are possible with fiber optic cabling technologies than with traditional copper systems. Data rates far exceeding the gigabit per second (Gbps) range and higher are possible, and the latest IEEE standards body is working on 100Gbps fiber based applications over much longer distances than copper cabling. Multimode is preferred fiber optic type for 100-550 meters seen in LAN network, and since single mode fiber optic cables are capable of transmitting at these multi-gigabit data rates over very long distances, they are the preferred media for transcontinental and oceanic applications.

3. Longer Maximum Distances

Typical copper media data transmission by the distance limits the maximum length of less than 100 meters. Because they do not suffer from the electromagnetic interference problems of traditional copper cabling and because they do not use electrical signals that can dramatically reduce the long distance, single-mode fiber optic cables can span 75 kilometers (about 46.6 miles) without using signal-boosting repeaters.

4. Better Security

The Copper cable transmission media is susceptible to eavesdropping through taps. A tap (short for wiretap) is a device that punctures through the outer jacket of a copper cable and touches the inner conductor. The tap intercepts signals sent on a LAN and sends them to another (unwanted) location. Electromagnetic (EM) taps are similar devices, but rather than puncturing the cable,they use the cable’s magnetic fields, which are similar to the pattern of electrical signals. Because fiber optic cabling uses light instead of electrical signals, it is immune to most types of eavesdropping. Traditional taps won’t work because any intrusion on the cable will cause the light to be blocked and the connection simply won’t function. EM taps won’t work because no magnetic field is generated. Because of its immunity to traditional eavesdropping tactics, fiber optic cabling is used in networks that must remain secure, such as government and research networks.

Disadvantages

With all of its advantages, many people use fiber optic cabling. However, fiber optic cabling does have a couple of disadvantages:

1. Higher Cost

The higher cost of fiber optic cabling has little to do with the cable these days. Increases in available fiber optic cable manufacturing capacity have lowered cable prices to levels comparable to high end UTP on a per-foot basis, and the cables are no harder to pull. Ethernet hubs, switches, routers, NICs, and patch cords for UTP are very inexpensive. A high quality UTP-based 10/100/1000 auto-sensing Ethernet NIC for a PC can be purchased for less than $25. A fiber optic NIC for a PC costs at least four times as much. Similar price differences exist for hubs, routers, and switches. For an IT manager who has several hundred workstations to deploy and support, that translates to megabucks and keeps UTP a viable solution. The cost of network electronics keeps the total system cost of fiber-based networks higher than UTP, and ultimately, it is preventing a mass stampede to fiber-to-the-desk.

2. Installation

The other main disadvantage of fiber optic cabling is that it can be more difficult to install. Ethernet cable ends simply need a mechanical connection, and those connections don’t have to be perfect. Fiber optic cable can be much trickier to make connections for mainly because of the nature of the glass or plastic core of the fiber cable. When you cut or cleave (in fiber optic terms) the fiber, the unpolished end consists of an irregular finish of glass that diffuses the light signal and prevents it form guiding into the receiver correctly. The end of the fiber must be polished and a special polishing tools to make it perfectly flat so that the light will shine through correctly.

Conclusion

From the above, we have learnt the advantages and disadvantages of fiber optic cable. Knowing the advantages and disadvantages of fiber optic cable can help us to choose a suitable fiber cable. For more details about fiber cables, please visit FS.COM.