Reference guide to fiber optic testing second edition volume 1 by j. And then it receives the return information at the otdr port. Otdr testing of fiber optic cable plants otdr testing creates a snapshot of a fiber optic cable. The otdr plots these fiber optic field testing guidelines excerpt from optical cable corporations installation guide page 3 of 6 occ2069 controlled document rev. By noting the timing of these reflections the otdr can. Vfl can be used to find direct defect locations in dead zones of fiber testing or to calibrate the fiber core in multifiber cables. Nov 02, 2016 otdr optical timedomain reflectometer is used to test the performance of newly installed fiber links and detect problems that may exist in fiber links. It also extracts, from the same end of the fiber, light that is scattered rayleigh backscatter or reflected back from points along the fiber.
Losslength certification heres what cabling professionals. Which is widely used in the construction, maintenance, measurement, emergency repair of opticalfibre communication system works. June 2010 field testing installed optical fiber cabling. Using an optical time domain reflectometer otdr 67. During the process of otdr testing, the equipment injects a higher power laser or fiber optic light source pulse into a fiber from one end of the fiber cable. The otdr basics poster provides a fundamental collection of technical information about otdrs and fiber testing. You can use an otdr tester to identify optical fiber. Connect the otdr to one end of a launch cable may also be called a dead band cable.
Fiberxpert otdr 5000 measures, documents and troubleshoots. Lanscape solutions recommended fiber optic test guidelines. I have been personally involved in several instances where misapplication of otdr testing has cost. The tberd 4000 is a highly integrated platform that features two module slots, a large 7inch color screen with a touchscreen option, a highcapacity lithiumion battery, an optional video inspection scope through universal serial bus usb port, and optional builtin optical test. Otdrs are valuable fiber optic testers when used properly. The fiberxpert otdr 5000 measures, documents and troubleshoots fibre optic networks and offers very high resolution enabling one of the shortest dead zones available for. This is why we prepared a webinar that covers everything related to otdr testing. The inservice otdr was designed specifically for testing live fiber networks. Now troubleshooting fiber and testing to the latest industry among various functions standards and customer specs is as quick and easy as pushing a button. Normally, for commissioning a new cable link, otdr testing is carried out in.
Optical time domain reflectometer test fiber otdr s are useful for determination of overall cable quality. A launch cable allows the otdr to settle down after the initial pulse and provides a reference cable for testing the first connector on the fiber under test. An otdr injects a series of optical pulses into the fiber under test. Cfo 301 standard for installing and testing fiber optics management, security or fire alarm systems, or any other communications link. Learn valuable fiber optic and otdr testing techniques, correct cleaning and inspection procedures for optical connectors, and industry bestpractices to get the work done right the first time. Use the data storage features of the otdr to save the trace using a unique file name. Otdr handheld optical time domain reflectometry is a new generation of intelligent opticalfibre communication instrument. But if you need to correct the fiber network parameters manually, you can still do it. Get a complete picture of take your fiber testing connectionrich fiber networks the optifiber certifying otdr is the optimal solution for fiber networks with short fiber links. Otdr is a popular fiber optic testing tool which can be used to test the fiber loss, and locate the faults in fiber optic links. Unlike otdr which measures the time of the incidence and the amplitude of the reflected pulses sent to the fiber optic cable to locate the faults, vfl uses powerful visible light at the 360 to 670nm wavelength injecting to a fiber to visually and directly locate the. Otdr testing has been made simple with the fiberxpert otdr 5000 fibre tester, as it has been designed with network installers and operators of enterprise networks in mind. In many of my previous articles on fiber optic testing, i have mentioned optical timedomain reflectometers otdrs. With over 20 years of designing and manufacturing experience, our line of modular and handheld otdrs is the fruit of highly precise optical engineering.
Basics of otdr optical timedomain reflectometer testing. An otdr optical time domain reflectometer is a measurement tool for analysing an optical fibers transmission quality. We want you to feel confident after your installation every cable has been placed accurately and that none were damaged during the installation process. Planning, specification, design and installation of fiber optic networks. The optical events include splice loss, connector loss, fiber attenuation, and faults. This dedicated device uses an outof band wavelength test wavelength far away from traffic wavelength to enable otdr testing without disturbing either the network transmitters or the receivers. An optical timedomain reflectometer otdr is an optoelectronic instrument used to characterize an optical fiber. It also extracts, from the same end of the fiber, light that is scattered rayleigh backscatter or. Fiber type this parameter is used to set fiber type which determines the gir and backscatter coefficient. Free online optic fiber and otdr training package syllabus. Otdr testing quick reference guide keys afl fiber optic. The purpose of it is to detect, locate, and measure elements at any location on a fiber optic link.
Testing is made simple and fast with the press of the auto test button. Ehu olqn wkdw wkh 276 630 fdqqrw yhq wkrxjk wkh 275 lv d srzhu ful tool is does not replace the need for tier 1 testing, because otdr testing results can vary as a result of user setup. If you made measurements and obtained the attenuation for the entire. An otdr is the optical equivalent of an electronic time domain reflectometer. Otdr optical timedomain reflectometer is such a powerful test instruments for fiber optic cable testing. Fiber optic measurements, otdr trace recording and. Wolszczak contact the authors jdsu 34 rue necker 42000 saintetienne france tel. May 24, 20 otdr working principle, we need to start from the process of otdr testing. Viavi first developed this particular otdr a few years ago, allowing. An allinone fttx test solution for rapid installation and maintenance of fiber networks. The otdr will display the distance from the otdr connector to the end of the fiber as well as the total loss of the span in db or the loss per kilometer. A receive cable provides a reference cable for testing the last connector of the fiber under test. The otdrs nondestructive, oneend connection and rapid measurement features, have made the otdr an indispensable tool for the testing of optical fiber during the construction and maintenance of fiber optic networks, as well as in. Jdsu pulse delay otdr method in the tberd mts6000 platform.
Testing is the most complex part of fiber optics but one of the most important. To locate the faults in fiber optic cables in a short time, various fiber optic testers are being invited to locate the faults of the fiber optic cable, like otdr optical timedomain reflectometer. Our company is working many years with otdr file format originally bellcore 1. Improper use, however, can be misleading and, in my experience, can contribute to expensive mistakes for the contractor. Licensed access only for highly experienced otdr operators looking to better understand concepts such as optical reflectance and back scatter, pressure points, gainers and ghosts. Manual measurement offers two ways to measure event loss. Dead zones are specified by otdr vendors at the shortest pulsewidth and are expressed in meters m. Maintenance and troubleshooting of a pon network with an otdr. You can use an otdr tester to identify optical fiber cabling. Optical time domain reflectometer the optical time domain reflectometer otdr is used to visually represent an optical fibers attenuation characteristics along its length. You can see the otdr trace overview in the new summary tab, which shows the total loss, the total distance, and the specified section parameters for your optical fiber. It injects a series of optical pulses into the fiber under test and extracts, from the same end of the fiber, light that is scattered rayleigh backscatter or reflected back from points along the fiber.
Testing and diagnosis of fiber networks tests of pmd, chromatic dispersion, return loss, otdr, optical power loss laboratory measurements, calibration and standardization in fiber optics. In premises applications, fiber optic cables can be used as the backbone cabling in a standard structured cabling network, connecting network hardware in the computer roommain cross connect. Do you know the fiber test method based on otdr technology. It locates defects and faults, and determines the amount of signal loss at any point in an optical fiber. Optical time domain reflectometer otdr testing an otdr works by injecting many pulses of light into a fiber and measuring backscattering and reflection of the pulses caused by imperfections in the fiber or interruptions in the fiber pathway from components such as connectors and splices. This otdr can be operated by the novice while at the same time appreciated by the seasoned user. This unit is available in dual singlemode, dual multimode and quad single wavelength versions. Whether install new fiber links or troubleshooting an existing network, the faster you can locate a problem, the faster you can fix it. Common issues that otdrs find are signal loss due to connector problems, fiber bends, crushes and breaks. Results from natural reflection of the fiber the otdr uses backscatter to measure fiber attenuation dbkm. Use same type of fiber and connector as futtesting 50125 mm fiber with 62,5125 mm reference cables gives virtually no losstesting 62,5125 mm fiber with 50125 mm reference cables gives 2 4 db losstesting sm fiber with mm reference cables gives 1520 db loss four ways to do the job sources of measurement uncertainty. Attenuation testing should be performed on each passive link segment of the cabling system.
The events are displayed as graphic and displayed on the lcd screen. Set the otdrs measurement mode to two point attenuation. Field test procedure for optical fiber link measurements sterlite. Ghost events in optical time domain reflectometer otdr. The light used for transmit signals over fiber optic is usually at 0 to 1650nm wavelength which is invisible to naked eyes. Acceptance testing of fiber optic cable using an otdr continued page 4 of 4 20, the light brigade, inc. Featuring an automatic event detection, all events on a fiber optic link are automatically.
Choosing the right optical time domain reflectometer otdr. Including their causes and how to measure and identify from an otdr trace using techniques such as multiwavelength and bi. Attach one end a of the cable to be tested to the launch cable. Raman and brillouin otdr measurements can be used to predict breaks and monitor fiber health by. Rayleigh otdr measurements are used for this technique, and while singleended unidirectional tests can be performed, dualended bidirectional otdr testing will improve result accuracy. Structured connectivity solutions field testing guidelines. Tier 2 is a complementary test to tier 1 and fiber inspection, and is recommended for proper documentation of the fiber infrastructure, and proof of work. The laser light is transmitted by multimode fiber only in the center of the core figure 9 because its emission angle is so low. Why should i average otdr results from both ends bidirectional averaging. An optical time domain reflectometer otdr for short is an electronicoptical instrument that is used to characterize optical fibers.
Otdr testing requires interpretation of the data acquired, called the trace or signature, by a skilled operator. An otdr needs access to only one end of the link and acts like an onedimensional radar system. Start the otdr and select the correct wavelength and refractive index for the test. Acceptance testing of fiber optic cable using an otdr by. It is mainly used to measure the attenuation decrease in light intensity of an entire optical fiber span, and to provide attenuation details relating to the total length of the span.
Lanscape solutions recommended fiber optic test guidelines lan1561aen page 3 guidelines wudfh fdq surylgh d ylvxdo slfwxuh ri wkh. Otdr, short for optical time domain reflectometer, is a fiber optic test equipment for characterize fiber optic network. Exfo otdr line exfo otdrs are designed for the field. Live fiber otdr inservice testing of pon requires out of band wavelength. An otdr is a fiber optic tester for the characterization of optical. Maintenance and troubleshooting of a pon network with an. Optical time domain reflectometer otdr is a widely used instrument in fiber optic testing. Oct 28, 2015 otdr handheld optical time domain reflectometry is a new generation of intelligent opticalfibre communication instrument.
The otdr only needs to have access to one end of a fiber to make its measurements. The purpose of otdr is to detect, locate, and measure optical events at any position in the fiber optic link. The term event refers to faults caused by faulty splicing, faulty connectors andor bends in the fiber. View 500 standard otdr kws electronic test equipment gmbh. Hfc hybrid fibercoax networks catv networks fiber optic lans and fddi. The fiberxpert otdr 5000 provides very high resoluti on with one of the shortest dead zones available for testi ng multi mode and singlemode. Corning cable systems optical time domain reflectometer otdr provides testing flexibility by combining a rugged platform with multimode, singlemode, or advanced testing modules. Display features press tabs to perform the following.
The fiber optic tdr is especially useful to determine overall cable length. It able to detect, locate and measure events at any location on the fiber optic network. To overcome otdr dead zone during fiber optic testing, launch fiber is being added between otdr and optical fiber link under test. Improved analysis of fiber sections with 2 or more close events. Launch cables are necessary for most otdr units because the otdr is effectively blind for some distance from the light launch point. Attach a stst splice bushing to the end of the launch cable. A complete testing strategy download pdf fiber is playing as increasing role in most network installations, driven by the need for higherbandwidth applications in data centers and backbone cabling system, as well as emerging lowlatency 5g and fttx deployments in service provider networks. Mar 15, 2015 otdr used in fiber network acceptance test. Otdr optical timedomain reflectometer is used to test the performance of newly installed fiber links and detect problems that may exist in fiber links.
What instruments are used for fiber optic testing how to perform basic fiber optic testing measurement uncertainty in fiber optic testing how to troubleshoot problems fiber optic tests this lesson, another extensive one, is on fiber optic testing. Reliable and accessible fiber links are the very foundation of a sound optical network. Otdr is the main instrument in the field of optical fiber testing technology, which is widely used in the maintenance and construction of optical fiber cable, and can be used to measure the length of the fiber, transmission attenuation of the optical fiber, joint attenuation and fault location. Otdr testing fiberxpert otdr 5000 fibre tester edp europe. Test methods for installed singlemode optical fibre cable links. Tier 2 testing with an otdr is frequently performed in addition to basic, tier 1 tests. Otdr used in fiber network acceptance test fo wiki. I have been personally involved in several instances where misapplication of otdr testing.
A link segment consists of the cable, connectors, adapters and splices between two fiberoptic termination units patch panels, information outlets, etc. There are hand held otdrs with a small screen and some special purpose otdrs that are made for specific applications like identifying cable cuts. What you need to know about otdr trace analysis and. The otdr can check for cable problems such as defective cables, splice problems, inadequate bend radius, fiber cable microcracks, etc. Launch cable launch cord a test cable used to connect the otdr to the near end of the link under test that is long enough to allow the otdr to measure the loss of the first connection. Fiber testing and otdr basics brett isley terriitory sales manager october 28, 2015. This test is commonly used to verify the quality of the installation and troubleshoot problems.
Dec 27, 2012 our company is working many years with otdr file format originally bellcore 1. It injects a series of optical pulses into the fiber under test and extracts, from the same end of the fiber, light that is scattered rayleigh. These might cost less, and sometimes sufficient for enterprise fiber testing applications. Fiber testing services of pmd, chromatic dispersion, otdr. Optical time domain reflectometer otdr is an instrument used to create a virtual picture of a fiber optic cable route. Reference guide to fiber optic testing lasertec, center for. The otdr has problems with multimode fiber, since it uses a laser source to get the high power necessary to cause high enough backscatter levels to measure. So in order to assess the integrity of the infrastructure, we need accurate and faster methodologies and testing devices. We want you to feel confident after your installation every cable has been placed accurately and that none were damaged during the. However, the otdr dead zone will affect the testing result and the application of otdr. The results are displayed on the 5 inch touch screen and can be analyzed and saved conveniently.
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