Manual measurement offers two ways to measure event loss. In combination with an otdr unit, the mainframe can test for breaks. User guide fastreporter data postprocessing software. Acceptance testing of fiber optic cable using an otdr continued page 2 of 4 20, the light brigade, inc. Defects can be attributed to the cable manufacturing process, shipping, the cable. Normally, for commissioning a new cable link, otdr testing is carried out in. Material and waveguide dispersion combine to cause cd in single mode fibers. Guidance for otdr assessment of fusion spliced single. To ensure uniformity and repeatability of results, there are a number of national and international standards or fiber optic test procedures fotp that seek to define a uniform methodology. Otdr working principle the otdrs operating principle is based on the measurement of the raleigh backscattering signal, generated by sending a high power optical pulse from the otdr through the optical fiber.
The otdr injects a short laser pulse into the optical fiber and then measures the backscatter and reflection of the light as a function of time. The amount of light scattered back to the otdr for measurement is quite small, about onemillionth of what is in the test pulse, and it is not necessarily constant. Advanced otdr testing this halfday course is a continuation of exfos fe1033 introduction to otdr testing, and covers advanced otdr analysis functions, as well as the postprocessing tools related to otdr testing. Chuck dykstra follow fluke networks canadian operations manager. An otdr is the optical equivalent of an electronic time domain reflectometer. An optical loss test set is a mainstay for testing fiber optic cabling. The megger insulation tester is a small, portable instrument that gives you a direct reading of insulation resistance in ohms or megohms. And if youve just completed a fibre installation of your own, otdr testing will allow you to certify that your new cabling meets the. Clean the ends of the reference cables with an isopropyl alcohol soaked wipe. Figure 2 complete otdr trace is available by pressing the f2 key.
The test is performed with a light source which produces a continuous wave at specific wavelengths connected to one end of the fiber. Otdr testing creates a snapshot of a fiber optic cable. Bidirectional otdr testing done correctly published on march 30, 2016 march 30, 2016 23 likes 4 comments. Otdr testing requires interpretation of the data acquired, called the trace or signature, by a skilled operator. An otdr is capable of measuring fibre lengths, losses, connector losses, splice losses and fibre defects. They are continuously updated with technological trends and keep close contact with several worldrenowned institutions, companies and scientists. Frequently asked questions on otdrs and hints on their use otdrs, also known by their technical name optical time domain reflectometers, are valuable fiber optic testers when used properly, but improper use can be misleading and, in our experience, lead to expensive mistakes for the contractor. Utilizing sophisticated algorithms, the equipment is able to calculate exact length and approximate loss. Display features press tabs to perform the following. Think of the otdr pulse as being a virtual source that is testing all the fibre between itself and. It can offer you an overview of the whole system you test and can be used for estimating the fiber length and overall attenuation, including splice and matedconnector losses.
Read the materials linked on each lesson plan and use the otdr simulator to practice analyzing otdr traces. This test is commonly used to verify the quality of the installation and troubleshoot problems. Example of a loss budget calculation for testing network links. I have been personally involved in several instances where misapplication of otdr testing has cost. Tier 2 fiber certification procedure bidirectional otdr testing is required to calculate the correct event loss values of the linkundertest and due to directivity that results from differences in diameter, backscatter, numerical aperture and index of refraction of the link and launch and tail fibers. 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. The intial trace shows the connector on the otdr end has high reflections, saturating the otdr and causing the baseline of the trace to decay slowly. The core diameter and cladding are chosen such that light will remain within the 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. Choosing between optical loss and optical time domain. And if youve just completed a fibre installation of your own, otdr testing will allow you to certify that your new cabling meets the quality and performance specifications you need.
Fiber testing and otdr basics brett isley terriitory sales manager october 28, 2015. It makes project setup much simpler by helping you quickly organize, edit, view, print, save or archive test results by job site, customer, campus building and more. Experts in fiber testing anritsus range includes the unique coherent otdr for testing submarine cables up to 12,000 km and the new uotdr, with performance that rivals traditional otdrs that are four times the size and more than double the price. The otdr only needs to have access to one end of a fiber to make its measurements. Otdrs test the overall length, loss and optical return loss of fiber optic cables or networks. It can verify splice loss, measure length and find faults.
This users manual explains the features, operating procedures, and handling. If otdr has been set in realtime test mode, the system will continuously refresh and test till you click. The otdr an optical time domain reflectometer otdr for short is an electronicoptical instrument that is used to characterize optical fibers. Configuring the otdr acquisition with optipulses mode. Download a free otdr simulator for pcs after you study this page, you can download a free otdr simulator to run on your pc. With projx management system, optifiber pro allows a project manager to define each users role, settings and the associated tasks to be performed transforming the otdr into an allinone fiber testing tool complete with. With projx management system, optifiber pro allows a project manager to define each users role, settings and the associated tasks to be performed transforming the otdr into an allin. For good insulation, the resistance usually reads in the megohm range. Start the otdr and select the correct wavelength and refractive index for the test.
An optical time domain reflectometer otdr analyzes the light loss in an optical fiber network. Otdr testing complete the entire lesson and take the quiz. Installing and testing fiber optics the fiber optic association. The olts tests for the total amount of light loss on the fiber link. Baldwin summary optical cable must be tested throughout the procurement and installation process to ensure that nrao receives a fiber transmission system without defects or added cost. In many of my previous articles on fiber optic testing, i have mentioned optical timedomain reflectometers otdrs. Fieldtesting procedure optical fibre cabling subsystem.
The megger insulation tester is essentially a highrange resistance meter ohmmeter with a builtin directcurrent generator. The optical time domain reflectometer otdr is useful for testing the integrity of fiber optic cables. Using manual measurement, there are two ways to measure event loss. If you are seeking information about file extensions, then you are in. The complete guide to electrical insulation testing. To print or create an electronic version of the report, follow the appropriate procedure on. A number of ways exist in which channels can combine to form a. Lanscape solutions recommended fiber optic test guidelines.
It is only 700 feet or 200 meters long, which is normally considered quite short for otdr analysis. An important aspect in maximizing an otdrs value is to properly plan its daytoday usage. A wide variety of otdr machine options are available to you, there are 425 suppliers who sells otdr machine on. The procedure shields or masks the detector from highpower fiber reflections, preventing detector overload and eliminating the need for detector recovery. Additionally, they detect, locate, identify and measure optical components in installed networks including fusion splices, optical connectors and pon splitters as well as faults such as breaks or tight bends causing high loss. The order in which the tests are to be performed is not particularly critical. Otdr, short for optical timedomain reflectometer, is an optoelectronic instrument used to characterize an optical fiber. Jdsu pulse delay otdr method in the tberdmts 6000 platform. Acceptance testing of fiber optic cable using an otdr continued page 3 of 4 20, the light brigade, inc. The otdr can measure both distance and attenuation. This is due to the fact that the light wave introduced into the fiber core has a fixed frequency.
Receive cable tail cord a test cable used to terminate the far end of the link under test that is long enough for the otdr to measure the loss of the last connection. Set the otdrs measurement mode to two point attenuation. You can merge test results into an existing linkware pc database and then sort, search and organize by any number of data fields or parameters. How do you make measurements of fiber length and attenuation or spliceconnector loss and reflectance. View and download viavi smartotdr 100 user manual online. View online or download viavi mts 8000 user manual. If otdr has been set in average test mode, otdr will perform average test over the link circuit of the optical fibre to be tested based on the preset conditions. Otdr test results yield misleading splice loss values in cases of heterogeneous. How does an otdr work differently from a light source and power meter or olts optical loss test set. Users manual for otdr iii safety terms used in this manual the warning sign denotes a hazard.
Historically, lspm test sets require manual calculations and subjective interpretation by experienced. The details in the information panel on the left side of the screen will change according to which measurement tool is active. Fiber optic system test procedures data systems performance engineering llc performs three tests in order to determine fiber optic cable adequacy. Understanding the physics and errors of the measurement. We have 1 viavi mts 8000 manual available for free pdf download. Dec 27, 2012 otdr testinggn netttest cma4000 otdrotdr optical time domain reflectometer technology is designed to provide a single ended test of any cable. It locates defects and faults, and determines the amount of signal loss at any point in an optical fiber.
To complete the testing process, comprehensive reports can be generated in. The otdr trace can be used for cable acceptance, splice and connector loss, docu mentation, troubleshooting, fault location, optical return loss and to measure the length of the system. Utilizing sophisticated algorithms, the equipment is able to calculate exact length and approximate loss of events along the cable span. Otdr testinggn netttest cma4000 otdrotdr optical time domain reflectometer technology is designed to provide a single ended test of any cable. Insert the other test cable into the power meter step four. Reflectance column displays or hides the reflectance column. Standards and recommendations of fiber optic systems. It calls attention to a procedure, practice, or the like, which, if not correctly performed or. Oct 28, 2015 if otdr has been set in realtime test mode, the system will continuously refresh and test till you click. There are a number of ways in which channels can combine to form a new channel. It also extracts, from the same end of the fiber, light that is scattered. Fiber testing services of pmd, chromatic dispersion, otdr. Its a bit of a mouthful, but it saves a whole lot of time when youre on a faultfinding survey of your fibre plant. Test methods for installed singlemode optical fibre cable links.
Part two power meterlight source testing a bidirectional endtoend test will be performed on each fiber in a span at 10 and 1550 m with a light source and power meter. Read here what the otdr file is, and what application you need to open or convert it. Otdr testing is specified to ensure a higher level of testing to provide quantitative measurements. For more examples of loss budget calculations, see the corning standard recommended procedure srp document number 003126 on the corning web site.
Best practices for testing fiber optics in the enterprise bicsi. Connections for testing the tap port links from the near end through a fan. Fs offers a range of otdrs, choose from a variety of costeffective otdrs. Otdrs are valuable fiber optic testers when used properly. It is easy to merge otdr test results with the other. I have been personally involved in several instances where misapplication of otdr testing. Ensure that your patchcord has appropriate connectors.
It allows the user gain practical hand on experience using an otdr by setting all common parameters such as wavelength, pulse width, trace duration and ior then taking a virtual trace in real time all from the computer desktop. Acceptance testing of fiber optic cable using an otdr by. User guide optical time domain reflectometer profiber. An optical timedomain reflectometer otdr is an optoelectronic instrument used to characterize an optical fiber. Using an optical time domain reflectometer otdr 67. 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. Improper use, however, can be misleading and, in my experience, can contribute to expensive mistakes for the contractor. Some fiber optic measurement procedures kingfisher.
A wide variety of otdr testing options are available to you, there are 600 suppliers who sells otdr testing on, mainly located in asia. Otdr, pc software or any program that supports the telecordia sr4731 universal otdr file format aka. The trace is calculated to provide realistic otdr simulation without. Needless to say, its extremely important to understand how to use these instruments correctly. Instructions of otdr test modes and parameters ftth. The analyzed data can provide insight into the integrity of the fibers, as well as any passive optical component such as the connectors, splices, splitters and multiplexers along the cable path. Connect the open ends of the cables together with a coupler. Some otdrs have two lasers to allow for testing fibers at two different wavelengths. Otherwise, it may result in imprecise test trace, even permanent damage for the otdr. This document is not intended to be training material for optical testing.
Lanscape solutions recommended fiber optic test guidelines lan1561aen page 3 guidelines wudfh fdq surylgh d ylvxdo slfwxuh ri wkh. An optical timedomain reflectometer otdr is an optoelectronic instrument used for testing the integrity of fiber optic cables an otdr injects a series of optical pulses into the fiber under test. Standards and recommendations for fiber optic systems. Mainframe handheld otdr, designed for the construction, turnup and maintenance of fiber networks.
Optical time domain reflectometry otdr primer optical fiber optical fiber is composed of a transparent, light carrying, core surrounded by a cladding. Testing fiber optic cables the osi reference model physical data link network transport session presentation application ethernet physical layer optical fiber, twisted pair, coaxial cable, sonetsdh, modem, rs232, etc ip, arp, ipx, x. After the measurements, you can use waveform editing to combine the best data of each. You can easily switch between the two with the press of a button. In this twostage procedure, an otdr trace does not replace the insertion loss measurement with a lspm tool but is used for complementary evaluation of the fibre link. Use the cursors and the measurement tool buttoms to determine the exact methods of both of these measurements. Test procedure for installed single mode fiber cable plant.
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