Category Archives: Fiber Optic Testers

How To Test Optical Loss with Light Source and Power Meter?

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In order to know how effectively your fiber optic cables are transmitting, you’ll need to test each one for optical loss. The term “optical loss” can also be called insertion loss, describes the difference between the amount of light sent into the transmitting end of a fiber optic cable, and the amount of light that successfully makes it to the cable’s receiving end. TIA-standards specify that you must measure optical loss using an optical power meter and the proper light source to certify an optical fiber cable. How to do that? This blog will tell you.

Introduction to light source
A light source is a device that provides a continuous wave (CW) and stable source of energy for attenuation measurements. It includes a source, either an LED or laser, that is stabilized using an automatic gain control mechanism. LEDs are typically used for multimode fiber. On the other hand, lasers are used for singlemode fiber applications.

Introduction to light source
The output of light from either an LED or laser source may also have the option of modulation (or chopping) at a given frequency. The power meter can then be set to detect this frequency. This method improves ambient light rejection. In this case, a 2 kHz modulated light source can be used with certain types of detectors to tone the fiber for fiber identification or for confirmation of continuity.

Introduction to power meter
The power meter is the standard tester in a typical fiber optic technician’s toolkit. It is an invaluable tool during installation and restoration. The power meter’s main function is to display the incident power on the photodiode.

Introduction to power meter
Transmitted and received optical power is only measured with an optical power meter. Optical loss must be measured with a light source. Connect one end of the fiber to the light source and the other end to the power meter. The light source sends a wavelength of light down the fiber. At the other end of the cable, the power meter reads that light, and determines the amount of signal loss.

Introduction to Testing Procedure

  • Connect the light source to the transmitting end of the test cable.
  • Connect the power meter to the receiving end of the test cable.
  • Turn on the source and select the wavelength you want for the loss test.
  • Turn on the meter, select the “dBm” or “dB” range and select the wavelength you want for the loss test.
  • Measure the power and loss at the meter.

Light Source and Power Meter

Cables with losses higher than 0.5 dB per end should be cleaned and retested. Dirt is always an issue. If any of the connectors are dirty, measurements will show higher loss and more variability. If the optical loss is still higher than 0.5 dB after cleaning, that means this cable is unqualified. Then you can discard it.

The Introduction of Optical Power Meter

What Is an Optical Power Meter?
optical power meterAn Optical Power Meter usually knows as Fiber optical power meter is a device that used to measure the absolute optical signal and relate fiber optic loss. The term usually refers to a device for testing average power in fiber optic systems. Fiber optical power meter is a tool for telecommunication and CATV network. Optical power meter consists of a calibrated sensor, measuring amplifier and display. The sensor primarily consists of a photodiode selected for the appropriate range of wavelengths and power levels. On the display unit, the measured optical power and set the wavelength are displayed. Power meters are calibrated using a traceable calibration standard such as a NIST standard.

When to Use Optical Power Meter?
When you install and terminate fiber optic cables, you need to test them. A test should be conducted for each fiber optic cable plant for three main areas: continuity, loss, and power. In order to do this, you’ll need a fiber optic power meter.

How to Use Optical Power Meter?
When you measure fiber optic power with a power meter, you should attach the meter to the cable. Turn on the source of power, and view the meter’s measurement. Compare the meter measurement with the specified correct power for that particular system to make sure it have proper power not too much or too little . Correct power measurement is so important to fiber optic cables because the system works similar to electric circuit voltage, and the power must be just the right amount to work properly.

Classification of Optical Power Meter
There are two types of Optical Power Meter: Ordinary Optical Power Meter and PON Optical Power Meter. Ordinary optical power meter measures the optical power in the fiber link, typically an absolute power value 850/1300/1310/1490/1550/1625nm optical wavelength. While PON Optical Power Meter is more suitable for measuring the fiber to the home (FTTH) networks. Specific measurement: PON Optical Power Meter can send three wavelengths from a single laser output port (1310 nm, 1490 nm, 1550 nm), of which 1310nm can measure upstream transmission direction, 1490 nm and 1550 nm measure downstream direction. Upstream associated with your upload data, downward is download data.

Tips for Selection and Operation

  • Choose the best probe type and interface type.
  • Evaluation of calibration accuracy and manufacturing calibration procedures, and your fiber and connectors to match the required range.
  • Make sure the type and the range of your measurement and display resolution is consistent.
  • With immediate effect db insertion loss measurements.
  • Wear eye protection when working with high-power cables. Even with low-power layouts, it’s wise to check the connectors with your power meter before looking.

Patch Cord Optical Power Loss Measurement

Measurement of fiber optic cable loss is an established practice that has been performed for many years. However over time, the performance of fiber optic equipment has improved, so occasionally it is useful to perform a practical re-assessment of the accuracy of these measurements.

Multimode patch cord optical loss power measurement is performed using the stpes described in ANSI/TIA-526-14, method A. The fiber optic patch cord is substituted for the cable plant. Because patch cords are typically no longer than 5m, the loss for the optical fiber is negligible and testing can be performed at 850nm or 1300nm. The loss meausured in this test is the loss for the patch cords connector pair. ANSI/TIA-568-C.3 states that the maximum loss for a connector pair is 0.75dB.

After setting up the test equipment as described in ANSI/TIA-526-14, method A, clean and inspect the connectors at the ends of the patch cords to be tested. Verity that your test jumpers have the same optical fiber type and connectors as the patch cords you are going to test. The transmit jumper should have a mandrel wrap or modal conditioner depending on the revision ANSI/TIA-526-14 being used for testing. Ensure that there are no sharp bends in the test jumpers or patch cord during testing.

Because both patch cord connectors are easily accessible, optical power loss should be measured in both directions. The loss for the patch cord is the average of the two measurements. If the loww for the patch cord exceeds 0.75dB in either direction, the patch cord needs to be repaired or replaced.

For testing the loss of a patchcord, you only need an 850 nm LED light source for multimode cable or 1310 laser for singlemode, a fiber optic power meter and some reference patchcords. Just remember that the patchcords used for references in testing must be good for tests to be valid, so you test them as you would other patchcords, just more often.

Testing patchcords is similar to testing any fiber optic cable. Use one reference patchcord to set a 0 dB reference. Connect a patchcord to test to the reference patchcord with a mating adapter. Connect the power meter to the other end of the patchcord and measure the loss. Since the length of the fiber is short, the loss contribution of the fiber is ignorable. And since one end of the cable is attached to the power meter, not another cable, you only measure the loss of the one connection between the reference cable and the cable under test, so you can test each connector individually.

To complete the testing of the patchcord, reverse the cable you are testing to check the connector on the other end. Sometimes you will find one bad connector and can replace it to make the patchcord useful again. But often the cost of replacing the connector may be higher than replacing the patchcord itself.

If your test equipment has different connectors than the patchcords you are testing, you will need hybrid reference cables with connectors compatible with the equipment on one end and the patchcord connectors on the other end. You will also need the correct connector adapters for your power meter.

Obviously, all reference cables used for testing must have high quality connectors to get reliable test results. Use this same method to test your reference cables against each other and discard any with high losses, usually those with losses over 0.5 dB.

Fiber Patch Cord Power Loss Measurement

Multimode patch cord optical loss power measurement is performed using the steps described in ANSI/TIA-526-14,method A. The patch cord is substituted for the cable plant. Becausepatch cords are typically no longer than 5m, the loss for the optical fiber is negligible and testing can be performed at 850nm or 1300nm. The loss measured in this test is the loss for the patch cord connector pair. ANSI/TIA-568-C.3 states that the maximum loss for a connetor pair is 0.75db.

After setting up the test equipment as described in ANSI/TIA-526-14, method A, clean and inspect the connetors at the ends of the fiber patch cords to be tested. Verify that your test jumpers have the same optical fiber type and connetors as the patch cords you are going to test. The ANSI/TIA-526-14 being used for testing. Ensure that there are no sharp bends in the test jumpers or patch cords during testing.

Because both patch cord connectors are easily accessible, optical power loss should be measured in both directions. The loss for the patch cord is the average of the two measurements. If the loss for the patch cord exceeds 0.75dB in either direction, the patch cord needs to be repaired or replaced.

Connector insertion loss measurement isolates the loss of a single connector on a cable assembly. It may be referred to as connector loss. Many time cable assemblies are shipped from the manufaturer with the insertion loss for each connetor listed on the packaging. The package shown in Figure 33.37 contains a duplex multimode patch cord. In the upper-left corner of the package, a label lists the insertion loss measurements for each connector.

Connector test jumper 1 as shown earlier in Figure 33.31. Record the optical power displayed by the optical power meter. This number is the reference power measurement. This number is typically around -20dBm with a 62.5/125μm multimode optical fiber and -23.5dBm with a 50/125μm multimode optical fiber. These numbers can vary from OLTS to OLTS. The following are 62.5/125μm and 50/125μm multimode fiber from fiberstore, picture is below:

SC-SC Multi mode

SC-SC Plenum Duplex 62.5/125 Multi-mode Fiber Patch Cable, with SC to SC termination, this fiber optic patch cable is specificially designed for ethernet, multimedia, or communication applications. The SC connector features a push-pull locking system. The plenum rating provides the fire protection required to run this cable within walls and air plenums without using conduit. The patented injection molding process provides each connection greater durability in resisting pulls, strains and impacts from cabling installs.

FC-ST

ST Fiber Cable connector has a bayonet-style housing and a long spring-loaded ferrule hold the fiber. They are available in both multimode or singlemode versions. Horizontally mounted simplex and duplex adapters are available with metal or plastic housing.

Fiber Optic Visual Light Testers from FiberStore

Visual fault locators can be part of OTDR, which is able to locate the breakpoint, bending or cracking of the fiber glass. It can also locate the fault of OTDR dead zone and make fiber identification from one end to the other end. Fiber optic visual fault locators include the pen type, the handheld type and portable visual fault locator. FiberStore also supply a new kind of fiber optic laser tester that can locates fault up to 30km in fiber optic cable.

The new visual fault locator fiber optic laser tester 30km is especially designed for field personnel who need an efficient and economical tool for fiber tracking, fiber routing and continuity checking in an optical network during and after installation. It can send fiber testing red light through fiber optic cables, then the breaks or faults in the fiber will refract the light, creating a bright glow around the faulty area. Its pen shape made it very easy to carry, and its Cu-alloy material shell made it sturdy and durable, 2.5nm universal interface make it more attractive. The inspection distance various according to different mode.

Features
Easy to check fiber faults with visual red laser light
FC, SC, ST General interface
Sturdy and durable shell
Constant output power
Long inspection distance
Operates in either CW (Continuous wave) or pulse (Both modes are available)
Pen pattern design, convenient for use and carry
Dust-proof design keeps fiber connectors clean

Compact in size, light in weight, red laser output, both SM and MM available

FiberStore provides enough stock of fiber optic visual light testers which usually be shipped out in a short time, and can be shipped out in 2-4 business days. We offer 1 years warranty for the quality of these products, so customers can place the order with 100% confidence!

Find Hidden Cables with Cable Wire Locators

Locating buried and hidden lines prior to construction or maintenance projects is critical to ensure the safety of your crew and reducing the potentially costly mistake. Cable locators and wire tracers are specially designed to aid in locating energized and de-energized wires, cable and pipes whether underground or hidden in a wall.

Cable locators are reply on the target having a charge or signal placed on them which is detected by a receiver within the locator, many locators are able to induce a signal onto the line using a transmitter in order to find it. Generally, the target must be metallic in order to conduct the signal, through a sonder or mini-transmitter can be used with plastic pipes. When induce a signal onto a pipe or cable, the transmitter is most commonly connected directly to the line or pipe to be located using signal clamps or clips. The signal will then transmit along the pipe or cable. In areas where there is no access to the line, the transmitter can also induce a signal from above, through the gourd to reach the utility.

Depending upon the application, there is a range of cable locators to be chosen. Some are designed for use for underground lines and pipes while other better suited for the tight confines of a walllikes wire trackers. Cable locators usually include a transmitter and a receiver. A widely used underground cable wire locator is NF-816, which is designed to locate the path of none-energized wirebehind walls or underearth. It can rapidly find the target wire from among plenty of telephone wires or network wires. By comparing the volume of the “tout” sound and the brightness of the signal indicator, you can find the target wire which has the highest volume and brightest indicator.

There are two primary methods of sweeping for lines and pipes with a cable locator: Passive locating involves sweeping an area looking for unknown lines while actively locating searching for a specific line by using either a direct connection or by inducing a signal. When using a cable locator to find underground lines and pipes, the underearth condition has a significant impact on the signal. Lays and camp solids help the signals travel down the line or pipe stronger with less interference than dry soils. So it is necessary to add water to the ground near the transmitter to improve signal strength.

Using Fiber Optic Power Meter to Test Optic Power Level

Fiber optic communication equipment is based on the optical power level between the transmitter and the receiver. The difference of the optical power level between them is the loss of the cabling plant. To measure the power loss of them, an optical power meter is needed to conduct a power loss testing.

fiber optic power meter is typically consist of a solid state detector, signal conditioning circuitry and a digital display of power. To interface to the large variety of fiber optic connectors in use, some form of removable connector adapter is usually provided. The power meter is calibrated at the same wavelength at the source output such as multimode 850 or 1300nm, single mode, 1310, 1490 and/or 1550nm, POF. Meters for POF systems are usually calibrated at 650 and 850nm. The wavelengths used in POF systems.

When performing the test, use the optical power meter adapter to mate to the connector type on the cable. The connectorized reference patch cables must be the same fiber type and size as the cable plant and have connectors compatible to those on the source and cables.

Power meters are calibrated to read in dB reference to one milliwatt of optical power. Some meters of a relative dB scale also, useful for loss measurements since the reference value may be set to 0 dB on the output of the test source. Occasionally, lab meters may also measure in linear units like milliwatts, microwatts and nanowatts.

Optical Power Testing Procedure:
Turn on the power meter to allow time to warm-up.
Set meter to wavelength of the source and “dBm” to measure calibrated optical power.
Clean all connectors and mating adapters.
Attach reference cable or fiber patch cord to source if testing source power or disconnect cable from receiver.
Attach power meter to end of cable and read measured power.

To reduce the measurement uncertainty, you must calibrate the optical power meter according the manufacturers specified intervals. Clean all connectors and remove the meter adapter periodically to clean the adapters and power meter detector. To avoid the stress loss, please don’t bend the fiber optic cables during the testing.

Optic power testing is only one the main part of fiber optic testing. Most test procedures for fiber optic component specifications have been standardized by national and international standards which are converted in procedures for measuring absolute optical power, cable and connector loss and the effects of many environment factors such as temperature, pressure, flexing, etc. Basice fiber optic testing instruments are the fiber optic power meter, optical light source, OTDR and fiber inspection microscope.

How To Install and Test the Fiber Optic Cables

In the telecommunications industry today, how to install the fiber optics that each optical engineer must learn in their work. Don’t froget, when you install the fiber optics, you must testing your fiber optic system. Optical-fiber testing is one of the final and most important procedures in installing optical networks.

How to install the fiber optic cable?

Fiber optic cable may be installed indoors or outdoors using several different installation processes. Outdoor cable may be direct buried, pulled or blown into conduit or innerduct, or installed aerially between poles. Indoor cables can be installed in raceways, cable trays,placed in hangers, pulled into conduit or innerduct or blown though special ducts with compressed gas. The installation process will depend on the nature of the installation and the type of cable being used. Installation methods for both wire and optical fiber communications cables are similar. Fiber cable is designed to be pulled with much greater force than copper wire if pulled correctly, but excess stress may harm the fibers, potentially causing eventual failure.

The install fiber optic cable tips:

a) Follow the cable manufacturer’s recommendations. Fiber optic cable is often custom-designed for the installation and the manufacturer may have specific instructions on its installation.
b) Check the cable length to make sure the cable being pulled is long enough for the run to prevent having to splice fiber and provide special protection for the splices.
c) Try to complete the installation in one pull. Prior to any installation, assess the route carefully to determine the methods of installation and obstacles likely to be encountered.

Testing fiber optic cables steps:

After installation, test each fiber in all fiber optic cables for verification of proper installation. Perform the following tests:
a) Continuity testing to determine that the fiber routing and/or polarization is correct and documentation is proper.
b) End-to-end insertion loss using an OLTS power meter and source. Test multimode cables by using TIA/EIA 526-14 Method B, and single-mode cables using TIA/EIA 526-7 (single-mode). Total loss shall be less than the calculated maximum loss for the cable based on appropriate standards or customer specifications.
c) Optional OTDR testing may be used to verify cable installation and splice performance. However, OTDR testing shall not be used to determine cable loss.
d) If the design documentation does not include cable plant length, and this is not recorded during installation, test the length of the fiber using the length feature available on an OTDR, or some OLTSs.
e) If testing shows variances from expected losses troubleshoot the problems and correct them.

FiberStore is a professional fiber optic cable manufacturer of broad range of fiber optic and copper data communication cabling and connectivity solutions primarily for the enterprise market, offering an integrated suite of high quality, warranted products which operate as a system solutions for seamless integrate with other providers’ offerings. We provide some fiber optic products inculding about simplex fiber optic cable, 10G fiber cable, fiber patch cable, fiber optic transceiver module and so on. Know more info about products or testers or fiber optics tutorial, pls visit our company: www.fs.com.

The Knowledge About Underground Wire Tracer

Why need the underground cable locator in our life. Because more and more underground cable as for the load was increased, their own aging and barbaric construction lead cable often fails is not the normal power supply, thus affecting the living and plant shutdowns, immeasurable loss is caused by the mining and other research units.Now an underground cable locator tester can help you to find the question cable.

FiberStore Underground Wire Tracer NF-816 can be used for testing different types of faults in cables like continuity, dislocation, open circuit, short circuit, cable pairing faults, or indications like shielding indication, straight cable/ cross over cable indication, etc. It can help us quickly to find the questions of the fiber optic cable.

About Underground Wire Locator:

The Underground Wire Tracer/Underground Cable Locator is designed to locate the path of non-energized wires behind walls and underground. The 816 is also capable of locating a specific circuit breaker, pinpointing wires before drilling and verifying dig sites underground. The effective range is up to 3 feet deep and up to 1000 feet in length.

Since its development, the unit consists of a transmitter, model 816T, is equipped with a thumb wheel switch for turning the unit on and adjusting the output level on the front of the unit for use with the large alligator clip leads. Push the switch to select to test”Cable Scan” or”Battery Test” The transmitter is constructed of high impact plastic and is powered by one 9V battery.

The receiver, model 816R, is equipped with a thumb wheel switch for turning the unit on and adjusting the receiver gain. The tracking antenna is attached to the receiver with a 3-foot long cable(such as Cat 7 patch cable). Also is equipped with a White LED light and a external earphone, The receiver has been designed to filter AC power related noise. The receiver is constructed of high impact plastic and is powered by one 9V battery.

The alligator clip leads are available to connect the transmitter to electrical wire, CATV coax, telephone drops, irrigation control wires or metallic pipes.

This locating system is packaged in a toolkit & box with extra batteries, external earphone and has operating instructions in the behind of the toolkit.

Key Features

  • Find wire on all types of connected operating Ethernet switch /Router/PC terminal
  • Rapidly find the target wire from among plenty of telephone wires
  • Rapidly find the target wire from among plenty of network wires
  • It can take place of cable tester
  • Compare the volume of the “tout” sound and the brightness of the signal indicator. Then you can find the target wire which has the highest volume and brightest indicator

Functions

  • Trace telephone wire/LAN cable
  • Trace wire in electrical system
  • Verify LAN cable condition
  • Continuity test
  • DC level testing function
  • Bright white LED flash light

Specification

  • Output voltage(open circuit): 9Vp-p
  • Carrier: 44.75KHz
  • Audio modulation: 900HZ
  • Battery: 9V DC
  • Battery Life (nominal):816T (35 hrs); 816R (20 hrs)
  • Size: transmitter: 49*125*33 mm receiver: 43*168*27mm
  • Color: yellow+ black

If you need any work that might risk you running into an electric cable, do yourself a favor and check first with the help of an underground wire tracer. For more info about Underground Cable Locator NF-816, or need some cheap fiber optic cable. Please contact the sales via sales@fs.com, we will answer your questions as soon as possible.

Understanding Fiber Optic Based Light Source

Each piece of active electronics will have a variety of light sources used to transmit over the various types of fiber. The distance and bandwidth will vary with light source and quality of fiber. In most networks, fiber is used for uplink/backbone operations and connecting various buildings together on a campus. The speed and distance are a function of the core, modal bandwidth, grade of fiber and the light source, all discussed previously. Light sources of the fiber light source are offered in a variety of types. Basically there are two types of semiconductor light sources available for fiber optic communication – The LED sources and the laser sources.

Using single mode fiber for short distances can cause the receiver to be overwhelmed and an inline attenuator may be needed to introduce attenuation into the channel. With Gigabit to the desktop becoming commonplace, 10Gb/s backbones have also become more common. The SR interfaces are also becoming common in data center applications and even some desktop applications. As you can see, the higher quality fiber (or laser optimized fiber) provides for greater flexibility for a fiber plant installation. Although some variations ( 10GBase-LRM SFP+ and 10GBASE-LX4) support older grades of fiber to distances 220m or greater, the equipment is more costly. In many cases, it is less expensive to upgrade fiber than to purchase the more costly components that also carry increased maintenance costs over time.

Light sources of the fiber light source are offered in a variety of types. Basically there are two types of semiconductor light sources available for fiber optic communication – The LED sources and the laser sources.

In fiber-optics-based solution design, a bright light source such as a laser sends light through an optical fiber, called laser light source . Along the length of the fiber is an ultraviolet-light-treated region called a “fiber grating.” The grating deflects the light so that it exits perpendicularly to the length of the fiber as a long, expanding rectangle of light. This optical rectangle is then collimated by a cylindrical lens, such that the rectangle illuminates objects of interest at various distances from the source. The bright rectangle allows line scan cameras to sort products at higher speeds with improved accuracy.

The laser fiber-based light source combines all the ideal features necessary for accurate and efficient scanning: uniform, intense illumination over a rectangular region; a directional beam that avoids wasting unused light by only illuminating the rectangle; and a “cool” source that does not heat up the objects to be imaged. Currently employed light sources such as tungsten halogen lamps or arrays of light-emitting diodes lack at least one of these features.