What Can We Get From Fiber Cable Jacket?

Fiber optic cable is applied as the most advanced communication medium by more and more users. Compared with copper cable, it can support more and better optical signal transmission of voice, data, video, etc. and offer many other advantages. When purchasing fiber optic cables, you must see the cable jacket at first. So what information does the outside jacket tell? What type of cable jacket should you select? Come with me to find the secrets of fiber cable jacket.

Fiber Cable Jacket Introduction

Fiber optic cable is constructed very complicated from the inside core, cladding, coating, strengthen fibers to the outside cable jacket. The core made of plastic or glass is the physical medium for optical signal transmission. As bare fiber can be easily broken, cable outer jacket is needed for fiber protection. The cable jacket is the first line of moisture, mechanical, flame and chemical defense for a cable. Without the jacket, fiber optic cables are very likely to be damaged during and after installation.

fiber-cable-jacket

Fiber Cable Jacket Characteristics

In most situations, robust cable jacket is better because the environment above or underground may be harsh. For better applications, you’d better take cable jacket seriously. Cable jacket is not as easy as you think. There are many characteristics you need to consider. Except the flexibility, it should withstand very low and high temperature. Whether the cable jacket has the good features of chemical and flame resistance. All these characteristics depend on cable jacket materials.

Fiber Cable Jacket Materials

Cable jacket is made of various types of materials. As mentioned above, the cable jacket should stand the test of different environmental conditions, including the harsh temperature, the sun & the rain, chemicals, abrasion, and so on. The following shows several common cable jacket materials for your reference.

PE (Polyethylene)—PE is the standard jacket material for outdoor fiber optic cables. It has excellent properties of moisture and weather resistance. It also has the good electrical properties over a wide temperature range. Besides, it’s abrasion resistant.

PVC (Polyvinyl Chloride )—PVC is flexible and fire-retardant. It can be used as the jacket materials for both indoor and outdoor cables. PVC is more expensive than PE.

LSZH (Low Smoke Zero Halogen)—LSZH jacket is free of halogenated materials which can be transformed into toxic and corrosive matte during combustion. LSZH materials are used to make a special cable called LSZH cable. LSZH cables produce little smoke and no toxic halogen compounds when these cables catch fire. Based on the benefits, LSZH cable is a good choice for inner installations.

Fiber Cable Jacket Color

Fiber cable jacket color depends on the fiber cable type. Fiber cable includes single-mode and multimode types. For single-mode fiber cable (Blog about single-mode fiber cable please read my blog What Are OM1, OM2, OM3 and OM4?), the jacket color is typically yellow. While for multimode cable ( more details on multimode fiber cable ), the jacket color can be orange (OM1&OM2 cable), aqua (OM3 cable) and purple (OM4 cable). For outside plant cables, the jacket color is black.

How to Choose Fiber Cables?

To choose a fiber optic cable depends on your own applications. I’ll talk about this from two sides of jacket color and jacket material. The cable jacket color is not just for good looking. Different color means different fiber mode. Which one suits you the most, the yellow or orange fiber cable? You should know well about the color codes before buying your fiber cables. What’s more, you should also consider the installation requirements and environmental or long-term requirements. Where will be your fiber cables installed, inside or outside the building? Will your cables be exposed to hash environment very long? This can help you decide which jacket material is the best.

Summary

As a popular data transmission medium, fiber cable plays an important role in communication field. To some degree, the success of fiber connectivity lies in a right fiber cable. How to buy suitable fiber optic cables? This article describes the method from cable jacket. When selecting fiber cable, many other factors still need to be considered. Hope you can get your own fiber cable.

Originally published at http://www.fiber-optic-equipment.com

Advice on Patch Cable Selection for Optical Transceiver

Fiber optic network connection can’t be achieved without fiber optic transceivers and fiber patch cables. Fiber optic transceivers vary from transmission media, interface, transmission distance, data rate, and brand, for example, SFP for 1000Mbps, SFP+ for 10G, QSFP+ for 40G, CFP and QSFP28 for 100G. It’s not difficult to identify these transceivers. But when you connect the transceiver to the patch cable, many details need to be noticed. This article will give you advice on how to choose the suitable patch cable for your transceivers.

Transmission Media—Copper & Fiber

According to transmission media of fiber optic and copper, transceivers can be divided into two kinds, copper based transceivers and fiber optic based transceivers. MSA has defined several copper based transceiver like: 100BASE-T, 1000BASE-T and 10GBASE-T. Copper transceivers are available in GBIC, SFP and SFP+ form factors, which usually has a RJ45 interface. So Cat5/6/7 cables are typically used to connect with the transceivers. Maybe Cat8 will be researched and developed to support higher data rate up to 40G sooner or later.

transceiver-rj45-interface

As to fiber optic transceivers, things are more complex. For that fiber optic transceivers require different fiber patch cords which have more types. Fiber patch cables cover single-mode and multimode. Single-mode patch cable can be classified into OS1 and OS2. While multimode cables can be divided into OM1, OM2, OM3, OM4 cable. Different cables are used in different applications. Single-mode cable can support long distance transmission and multimode cable for short distance link. If the transmission distance is shorter than 500 meters, multimode patch cable is suggested. For long distance transmission, single-mode transmission is suggested. You fiber-patch-cordsshould also consider that the transmission data rate can also affect the transmission distance. Let’s look at the following point.

Supported Distance and Data Rate

MSA has defined a variety of transceivers that can support different transmission distances and data rates. When you buy a fiber optic transceiver, you will find the data rate, wavelength, distance, etc. on its labeling. The following table show the basic information of most often used transceivers and supported cable type.

Description Wavelengh Data Rate Cable Type Distance
SX 850nm 1G MM 500 m
LX 1310nm 1G SM 8 km
EX 1310nm 1G SM 40 km
ZX 1550nm 1G SM 70 km
SR 850nm 10G MM 300 m
LR 1310nm 10G SM 10 km
ER 1550nm 10G SM 40 km
ZR 1550nm 10G SM 80 km
SR4 850nm 40G MM 100 m
SR10 850nm 100G MM 100 m
LR4 1310nm 40G SM 10 km

As mentioned before, single-mode patch cable is better for long distance transmission and multimode patch cable for short distance transmission. Actually single-mode patch cords can be used for different data rates in both long and short distances. But single-mode fiber optic cable will cost more. To achieve reliable performance in short distances with cost effective solutions, you should know the performance of multimode fiber optic cables. The following chart provides the detailed transmission distances and data rates information for different multimode fiber optic cables over wavelength of 850 nm for your reference.

Fiber Type 1G 10G 40/100G
OM1 300 m 36 m N/A
OM2 500 m 86 m N/A
OM3 1 km 300 m 100 m
OM4 1 km 550 m 150 m
Transceiver Interfaces

The selection of patch cable for transceiver should also consider the interfaces through which patch cords is connected to the transceiver. In addition, transceiver usually used one port for transmitting and one port for receiving. Generally, fiber optic transceivers usually employs duplex SC or LC interfaces. However, for BiDi transceivers only one port is used for both transmitting and receiving. Thus, simplex patch cord is used with BiDi transceiver.

Some 40G/100GBASE QSFP+ transceivers used MTP/MPO interfaces, which should be connected to the network with multi-fiber patch cords attached with MTP/MPO connectors. If these ports are used for 40G to 10G or 100G to 10G connection, then fanout patch cable should be used. For example, a MTP to 8 LC fanout cable can splitter 40G data rate to four 10G data rate.

Summary

Next time when you select patch cords for your fiber optic transceivers, you can consider these factors like transmission media, transmission data rate and distance, transceiver interfaces. FS.COM offers a wide range of fiber optic transceivers and patch cords. Custom service is also available. Any problem, please contact us via sales@fs.com.

Originally published at http://www.fiber-optic-equipment.com

Secrets of Choosing Fiber Rack Mount Enclosure

Fiber rack mount enclosures can provide a high-density solution for inter-connects or cross-connects between backbone horizontal cable and active equipment. Enclosures allow for easy field termination of connectors or installation of pre-terminated solutions, and are ideal for high-density fiber applications in data centers, equipment rooms, and central offices. Fiber rack mount enclosures come in different configurations. You may find fiber enclosures in the market with different sizes, slide-out or lid type, fixed front panel or removable front panel, splice tray or preterminated. Among so many types, you have to choose one that suits your application the most. So how to make the right decision? The following will tell you the method.

fiber-enclosure-loaded

Which Size of Rack Mount Enclosure?

The rack mount units are designed for rack mounting in 19-in (48 cm) racks. They are available in rack space options of 1U (two panels, cassettes or modules), 2U (four panels, cassettes or modules), 3U (six panels, cassettes or modules) and 4U (twelve panels, cassettes or modules), etc.(See the following picture.) You should choose the most proper one depending on the space and port requirement of your project.

rack-sizes-rack-units

Slide-out Type or Lid Type?

The rack mount enclosures include two kinds. One is the slide-out type, and the other incorporates a removable lid. The slide out type is more expensive while the lid type is less expensive but requires the user to remove the whole enclosure from the rack to gain internal access. If your budget is sufficient, I will recommend you to use the slide-out type. Then you may get more benefits during installation and maintenance, as they respectively feature a convenient slide-out support tray and a integrated swing-out tray so that you don’t need to remove the whole enclosure from the rack to gain internal access.

Fixed Front Panels or Removable Front Panels?

As we know, fiber optic adapters are the key part of an enclosure to accept the various fiber optic connectors. Thus, to choose a proper front panel option is also important. For general rack mount enclosures, there are mainly two types—one type uses fixed 1U High 19” front panel, and the other type incorporates three, or even up to five removable front panels. The latter is now becoming more popular with users, because a plug & play fiber adapter panel solution assures flexibility and ease of network deployment and MAC (moves, adds, and changes).

Splice or Pre-terminated?

Pigtail splicing and pre-terminated assemblies are the two basic way to do fiber termination. Depending on which method you choose, there are some differences in the rack mount enclosure selection. For pigtail splicing, you may need a rack mount panel with fiber splice tray, which are used for efficient management and storage of the spliced optical fibers. Splice tray is used for efficient management and storage of the spliced fiber optic cables. Fiber optic adapters are installed into the cut outs in the enclosure to accept the various fiber optic connectors. Fiber optic pigtails mate with the adapters and the fusion-spliced tails are stored on the splice tray.

But if you apply pre-terminated assemblies, the inner configuration of the rack mount panel is only the spools that are used to organize the cables. Obviously, the pre-terminated solution will help you save more installed time and labor cost.

Conclusion

In this article, you are advised to select the best fiber rack mount enclosure suitable for your own application from so many types. There are a wide range of rack mount enclosures in the market, which is good for interconnect and cross-connect in building your data centers. It’s ideal for the organization and protection of optic backbone terminations.

Originally published at http://www.fiber-optic-equipment.com

Dos & Don’ts of Cable Management

Just imagine how would you feel when you face cable spaghetti? You must say, “oh, it’s very annoying.” Yes, that’s right. Improper cabling can bring disadvantages like heat retention, untimely hardware failure and maintenance headaches. So how to avoid cable spaghetti and keep network cabling in a good organization?

nice-cabling

Since cable management is one of the most important factors of data center design, it’s necessary to master some cabling skills. The following content will give you some suggestions for cabling installation.

Don’t Pull Fiber Jumper Cables too Hard

When installing cables, pulling issue can’t be avoided. Pulling cables too hard can damage them by stressing the core. Stressing the core will affect the signal performance. In extreme cases, it will cause unwinding of the twists in the sheath. Under this situation, you should better buy high quality patch cords from reliable manufacturers or vendors. Good patch cords are able to withstand the stress. Because cheap cables have sub-standard sheathing and narrow diameter cores which can cause signal loss. A smaller core is also more fragile and weak, more likely to bend, leading to an increased rate of cable failure.

Don’t Ignore Labels

Cable labels are very likely to be ignored by engineers. After finishing cable installation, they always think they can remember every cable type, including the network cables, power cables, patch cables, etc. Things doesn’t happen like you wish. Your memory will disappear as time goes on. Thus, you should not overlook labeling which can help you identify cables in a short time and leave messages to other installers to easily decipher what goes back.

cable-label

Don’t Forget Cable Ties

Cable ties are cheap and useful to get a clean look of your data center. Today there are many categories in different sizes with many colors. Nylon and Velcro ties are the most two common kinds. Velcro ties are better than plastic ties because they are easy and quick to add, remove and reusable. Nylon cable ties can put mush stress on cable bundles and cause pressure points on the cable jacket, changing the cable geometry and thus decreasing performance. What’s more, Velcro ties can be cut easily to any length you need.

Measure the Exact Cable Length You Need

Usually it says the longer, the better. But it’s another case for network cabling. Improper cable length often causes cable mess. Suppose you have bought 50m patch cable. However, you just use 20m. Then how to deal with the spare 30m cable? Just leave it alone? Of course not. So you’re advised to measure the exact cable length you need. Custom cable is the best solution for you to get the right length.

Leave Space for Cables Trays

What if very long cables are left in your network system? You may consider to put the cables into the cable trays. But it’s not a good idea. Cable trays should not be overloaded. Suspended cable trays are mounted to a rack or something. If it’s too heavy, the cable trays may fall off and break other expensive things. Too many cables is not only safety problem, but also leads to poor operational practices because it’s too hard or fear of disturbing cables. What’s worse, the cables at the bottom of cable try may be crushed and degrade signal propagation.

Choose a Proper Cable Manager

Cable manager is an economical and efficient solution to manage high density structured cabling in data centers and telecommunication rooms, which allows the maximum amount of cables to be organized in a minimum amount of space. Choose the best cable manager which suits the most for your application. Simple or complex cable manager, vertical or horizontal, plastic or metal, one must meet your requirements for network cable management improvement.

cable-manager

Conclusion

Cable management is not an easy work. Some engineers may not take cable management seriously or they don’t care much if there is a little mess. But the improper operation can cause lots of problems. To achieve neat cabling, too many things must be taken into consideration. And some useful tools and equipment are also required. Come and find a perfect cabling solution.

Originally published at http://www.fiber-optic-equipment.com

Suggestions for Data Center Design

The demands on data centers and networks are growing very fast. To meet communication needs, more and more devices are connected to the data center network links. It brings difficulties in data center management. The infrastructure design should guarantee the reliable network performance. But how to achieve the best performance? Four suggestions are recommended for you when designing a data center.

Maximizing Network Performance

As today, many companies adopt high density configurations and virtualization to increase the capacity of existing IT equipment. To ensure the network performance, a robust data center infrastructure is necessary. And three parts of the infrastructure must be considered: the structured cabling, racks and cabinets, and the cable management.

data-center

Figure 1. Structured data center

First, the structured cabling performance has a close relationship to the connectivity and cable components. If the components fail to deliver good cabling system, great optical loss will be caused. To improve the channel performance, insertion loss should be minimized especially in 40G and 100G data center. Second, choose right rack or cabinet to accommodate new equipment with different size and weight requirements since active equipment in the infrastructure turn to be broken easily and will be replaced in five years or less. Third, manage the airflow and maintain good cooling system. Because the rising temperature of the data center has an influence on network performance. The last component of the infrastructure is cable management. A well-designed cable management should meet the standards of spare space, high reliability and scalability. The infrastructure is designed for both copper and fiber, maintaining proper bend radius for both copper and fiber, protecting cable from damage, and creating crosstalk and return loss.

Saving Time

Although data center grows in size and complexity, it often requires faster deployment. It must adapt to the rapid changing business requirements. As it says, time is money. Selecting an infrastructure that optimize time, result in faster deployments can save lots of costs.

In order to save time in deployment, installation and future moves, adds, and changes, a suitable modular solution based on the rack or cabinet should be applied. The modular solution is also good for effective airflow management and cooling, which can save time because it can easily support high density when needed. Pre-terminated copper and fiber cabling solutions can also save time during installation and future cabling moves. Pre-terminated fiber systems, for example, MPO to MPO trunk cables or MPO to LC harness cables, can facilitate the migration to higher speeds.

Optimizing Spare Space

To adapt to high speed demands, data center infrastructure turns to be more complex. Now space is a premium in the data center as port densities continue to increase. Considering the cost, infrastructure should be optimized for greater flexibility and scalability. High density connectivity options including high density patch panel, MTP cassette, etc. are the solutions to optimize space while supporting large port densities. For instance, LC connectors (2 fiber) have been replaced by MPO (typically 12 or 24 fibers) connectors for the migration from 10 GbE to 40 GbE and 100 GbE.

MTP-solution

Figure 2. MTP components for saving space

To optimize space in the data center, the following factors are needed to be considered:

  • Choose the rack or cabinet as your basic building block
  • Select racks and cabinets with higher weight limits, sufficient depth and heights that support growing vertically
  • Select cable management that can support existing and future cable density, fluent airflow, and is designed to support both copper and fiber
  • Select connectivity that supports high density and mixed media
  • Use cable with small outside diameter
  • Consider patching outside the rack and cabinet to save space for equipment
  • Select a rack or cabinet solution that easily integrates with overhead pathways
Finding a Cooperator With Rich Experience

During the design phase, the data center design must provide guaranteed performance while providing flexibility and scalability for future needs. During the installation phase, the solution must be easy to install, quick to deploy and easy to manage. So it’s important to find a qualified contractor who has a history of quality installations. You also need to choose a good manufacturer providing cost-effective components covering cooling, power, connectivity, cabling, racks and cabinets, cable management, and pathways, like Fiberstore (FS.COM). And the manufacturer should also have expertise of extending the equipment life, reducing cost and solving other problems in the data center.

Summary

Data center design is not an easy job as the cabling infrastructure becomes more complex for meeting the growing high data rates demands. To maximize the efficiency of a data center, too many elements should be taken into consideration. The above content gives suggestions for data center design to guarantee performance, save time, optimize space, and find an experienced cooperator. Hope this article is useful to your data center design.

Originally published at http://www.fiber-optic-equipment.com

MTP Trunks Assembly for High Density Data Center

The need for high bandwidth has never stopped. High bandwidth means more fibers are needed for the cabling infrastructure. The demands certainly change the network architecture to be more complicated. For spine-and-leaf architecture, each leaf switch in the network is interconnected with every spine switch. As a result, with leaf-spine configuration in data centers, fiber counts can multiply very quickly compared with traditional three-layer distribution architectures.

Besides, 40GbE and 100GbE grow quickly in the data center. Relatively, the interface of parallel optics like 40G QSFP+ changes to be MPO/MTP with 12-fiber instead of duplex fiber. And that also increases the fiber counts in your data center structured cabling. As data center evolves, links require 144 fibers, 288 fibers or even more. So data center managers are in front of many challenges such as limited space, deployment efficiency and of course the cost.

MTP Deployment Solutions

To address these challenges, many data center cabling designs use MTP trunks with up to 144 fibers. In data centers requiring more than 144 fibers, multiple runs of a 144-fiber cable assembly are typically installed to achieve the total desired fiber count. For example, if a link requires 288 fibers from the main distribution area of the data center to another location, two 144-fiber trunk cables would be installed. This method can reduce the physical space capacity for future growth. Figure 1 depicts the space savings across three deployment scenarios in a 12-inch x 6-inch cable tray with a 50 percent fill ratio:

  • 4,440 total fibers using 370 x 12-fiber MTP trunks
  • 13,680 total fibers using 95 x 144-fiber MTP trunks
  • 16,128 total fibers using 56 x 288-fiber MTP trunks

comparison

Figure 1. Comparison of trunks with different fibers

MTP connectivity is one of the important solutions used in high density environment. MTP cable allows for the deployment of optical fiber termination of 12 fibers at a time rather than individual termination of single fiber strands. In addition, this kind of cabling is easy for future migration to 40/100/200/400GbE networks using parallel optical technologies. To achieve high-fiber-count cable and connectivity, various implementation options are available.

MTP Trunk Assemblies

MTP trunk cable assemblies are offered in fiber types in standard 12, 24, 48, 72, 96 or 144 core versions in a compact and rugged micro-cable structure. With high port density, it brings big savings in installation time and cost. Due to its discreet premium connectors and special fiber, it delivers low insertion loss and power penalties in high speed network environment. And the multifiber connector and compact dimension also ease the space pressure in costly data centers.

MTP trunk cables are available in either mesh bundles or distribution fan-out trunks since infrastructure designs, cabling environments and pathway types are different, MTP connectivity in backbone cabling can employ different methods. Below are two possibilities:

Cables that are factory terminated on both ends using MTP connectors (MTP-MTP trunks)
Cables that are factory terminated on one end using MTP connectors (MTP pigtail trunk)

MTP-trunks

Figure 2. MTP assemblies types

MTP-MTP Trunks

MTP trunk assemblies are used where all fibers are landed at a single location at each end of the link—for example, between the main distribution areas (MDAs) and the server rows or between the MDA and the core switching racks in a computer room or data hall, as Figure 3 shows. Additionally, MTP-MTP trunks also appear between MDAs of multiple computer rooms or data halls where open tray is the pathway.

same-computer-room

Figure 3. MTP-MTP trunk assembly deployed in a computer room

MTP Pigtail Trunks

MTP pigtail trunks can be used for environments where the pathway doesn’t allow for a pre-terminated end with pulling grip to fit through—for example, a small conduit space (see Figure 4). This approach is common when needing to provide connectivity between MDAs of multiple computer rooms or data halls. Additionally, a deployment using pigtail trunks can be useful when the exact pathway or route is not fully known, avoiding exact length measurement before ordering of the assembly.

two-computer-rooms

Figure 4. MTP pigtail trunk field terminated in two computer rooms

Conclusion

Many factors should be considered to plan and install a data center cabling infrastructure for actual and future needs, especially in high density environments. So before choose the best cabling installation solution, you need to take following points into concern:

  • Application environment: inside or between computer rooms or data halls
  • Design requirements: traditional three-layer or spine-and-leaf architecture
  • Future proofing: transition path and future-technology support

From this article, high-fiber-count MTP trunks are the best solution for your backbone cabling. MTP trunks is useful for faster installation, lower pathway congestion and greater efficiency while delivering the bandwidth to meet the needs of 40GbE/100GbE/200GbE and beyond.

Originally published at http://www.fiber-optic-equipment.com

MPO Cables Testing Method

As the migration to 40G/100G Ethernet using parallel array transmission systems, the high-density MPO cables are widely used in the data center. In the connection, contamination even as small as 0.001 mm can cause the optical loss. Mating a contaminated connector to a clean connector will lead to poor performance and can damage the connection. So it’s important to test the link segments consisting of MPO array cabling and keep the cable clean. However, MPO cable testing and cleaning is full of challenges.

Why MPO cables testing and cleaning is not easy? First, MPO connectors are very sensitive to dirt and contamination. The ferrules are large and hard to clean and inspect. Most microscopes don’t have adapters for MPO connectors. Those microscopes with adapters for MPO connectors can only see a small section of the ferrule because they are adapted from single fiber microscopes. So you have to inspect the entire ferrule and every fiber. Second, cleaning is also a problem because of the designs of MPO connectors with pins and holes. Most dry cleaners can only clean the place between the pins. So dirt may increase around the pins or in the holes, which cause alignment problems. So remember often keep MPO connectors well covered and protected when not in use.

Calculate the Acceptable Attenuation

Calculate the acceptable total loss of the entire optical link so that you can find if the test result is good or bad. Do as the following steps with your link loss calculator:

  • 1. Select the fiber type and test wavelength combination;
  • 2. Select the unit of length in feet or meters;
  • 3. Enter the total link length under test;
  • 4. Enter the number of connections of each type (a pair of connectors counts as one connection);
  • 5. Enter the number of splices (each connection counts as a connection plus a splice).
MPO Trunk Cable Testing Procedures

In this case, MPO connectors can be directly connect to the test equipment. That requires 12 output sources and either 12 input ports or an MPO port with a detector which can accept the light from 12 or 24 fibers. But at present this is not available. In the laboratory or factory settings, there are test equipment that can achieve this. Then, engineers use an MPO to LC fan-out cord to separate the trunk into single fiber channels for testing.

There are five basic steps for an MPO trunk cable testing (see figure 1):

MPO testing

Figure 1. set reference (three pictures above) and test MPO cable (two pictures below)

  • 1. Find a test equipment where the input port can be changed to an LC or has an LC already.
  • 2. Set a reference and there are three methods. Insert the known good cords into relative input ports and run an autotest (the above three pictures). If the loss is fewer than 0.1 dB (usually the maximum loss of LC connection is 0.2 dB), then the reference cords are good. This is critical to the test.
Reference Method Reference Cable Connectors Included in Measurement Estimated Reduction in Measured Loss Estimated Increase in Errors
1-Cable Method(test equipment compatible with connectors being tested) 1, launch 0 0 dB 0 dB
2-Cable Method(single fiber ferrule connectors, test equipment not compatible with connectors being tested) 2, launch and receive 1 0.2-1 dB +/-0.2 dB
3-Cable Method(male/female or plug and jack connectors, test equipment compatible with connectors being tested) 3, launch, receive and “golden cable” 2 0.3-1.5 dB +/-0.25 dB
  • 3. After setting the reference, remove the middle test reference cords and connect fan-out cables with an MPO trunk cable.
  • 4. Measure and record the loss every pair of LC connectors at the left side.
  • 5. Measure and record the loss every pair of LC connectors at the right side.
Summary

Compare the test result with calculated acceptable attenuation, If the test result is not ideal,that may be caused by the contamination, defects in the cable plant, or improper test equipment usage. Then you should better check connector end-faces for dirt and defects, and check link segment for broken fiber, poor splices and tight bends. MPO connectors are very likely to be contaminated because of fibers, number of connections and tight loss budgets. To keep MPO cabling system perform well, frequent cleaning and inspection with one-click cleaner are required.

Originally published at http://www.fiber-optic-equipment.com