mikofy
optical components information and news
mikofy
暱稱: mikofy
性別: 男
國家: 美國
地區: 其他地區
« July 2026 »
SMTWTFS
1234
567891011
12131415161718
19202122232425
262728293031
最新文章
Discover the Best Ch...
Fashion Chrome Heart...
How to Choose Chrome...
What we should pay a...
Jacket Material Of B...
文章分類
全部 (185)
Optic fiber cable (1)
未分類 (184)
訪客留言
最近三個月尚無任何留言
每月文章
日誌訂閱
尚未訂閱任何日誌
好友名單
尚無任何好友
網站連結
尚無任何連結
最近訪客
最近沒有訪客
日誌統計
文章總數: 185
留言總數: 0
今日人氣: 11
累積人氣: 22360
站內搜尋
RSS 訂閱
RSS Feed
2013 年 9 月 6 日  星期五   晴天


Common Bulk Fiber Optic Cables Description 分類: 未分類

Fiber optic cables are widely used in modern, gradually replace of copper cables.

Key Specifications Of Fiber Optic Cables

·Transmission rate of 100 Mbps;
·Cable length of 2 kilometers or more;
·Not affected by electrical interference;
·Supports voice, video, and data;
·Provides the most secure media;
·Commonly used in backbones between buildings and Token Ring networks;
·Specifications for fiber include the IEEE's 10BaseFL (Ethernet) and ANSI's FDDI or Fiber Distributed Data Interface (Token Ring).

Depending on the number of fibers and how and where it will be installed, bulk fiber optic cables come in lots of different types. Choose cable carefully as the choice will affect how easy it is to install, splice or terminate and, most important, what it will cost! Such as tight buffered fiber cable and loose tube cable. Loose tube cable majority used in outside-plant installations, while tight-buffered cable primarily used inside buildings.

Tight Buffered Cable

Tight buffered (coated with a 900 micron buffer over the primary buffer coating) with Kevlar (aramid fiber) strength members and jacketed for indoor use. The jacket is usually 3mm (1/8 in.) diameter. Zipcord is simply two of these joined with a thin web. It's used mostly for patch cord and backplane applications.

Single-mode tight-buffered cables are used as pigtails, patch cords or jumpers to terminate loose-tube cables directly into opto-electronic transmitters, receivers and other active and passive components. Multimode tight-buffered cables also are available and are used primarily for alternative routing and handling flexibility and ease within buildings.

Distribution Cables

Distribution Cables contain several tight-buffered fibers bundled under the same jacket with Kevlar strength members and sometimes fiberglass rod reinforcement to stiffen the cable and prevent kinking. These cables are small in size, and used for short, dry conduit runs, riser and plenum applications. The fibers are double buffered and can be directly terminated, but because their fibers are not individually reinforced, these cables need to be broken out with a "breakout box" or terminated inside a patch panel or junction box. They can be multimode distribution indoor cable, single mode plenum distribution indoor cable, multimode plenum distribution indoor cable, waterproof cables, etc.

Loose Tube Cable

In a loose-tube cable design, color-coded plastic buffer tubes house and protect optical fibers. A gel filling compound impedes water penetration. Excess fiber length (relative to buffer tube length) insulates fibers from stresses of installation and environmental loading. Buffer tubes are stranded around a dielectric or steel central member, which serves as an anti-buckling element. The cable core, typically surrounded by aramid yarn, is the primary tensile strength member. The outer polyethylene jacket is extruded over the core. If armoring is required, a corrugated steel tape is formed around a single jacketed cable with an additional jacket extruded over the armor.

FiberStore covers a wide production line of bulk fiber optic cable, from common bare fiber, waterproof cables to special fiber cables for specific applications. Flexible or rigid cables of copper or aluminium, with a complete range of polymers and protectors, always developed under the most stringent international standards.



2013 年 8 月 21 日  星期三   晴天


Why Choose the Shielded Cabling System 分類: 未分類
Shielded VS. Unshielded
 

In Copper Cabling system at all levels, there are two main technical types: Shielded and Unshielded cabling systems. Since the earliest fabric cabling standards since its establishment types on these two technologies are widespread in the market. Germany, Australia, Switzerland and France in the first preference or relatively shielded cabling system, while in other parts of the world, the more popular non-shielded cabling system and will soon be adopted. Both shielded and unshielded gigabit transfer rate to meet the requirements, but when the transmission rate up to Gigabit or even higher, the shield system to support the stability of the advantages of the high frequency transmission becomes very apparent.

Cable structure

 
What is the function of shielded?
 
F/UTP
 
F/UTP cable shielding structure is four pairs of wires in the data cable outside the contractor a layer of aluminum foil shielded, this layer of shielding can be reduced to a great extent the total package:
 
1. This is the root of the signal transmission cable radiated interference signals on the impact of adjacent data cable (for example: the same bundle of cables in the adjacent data cable).
 
2. Interference from other data cable or other interference source signal for this cable.
 
3. For a high quality data transmission system, which is significant in two kinds of effects. If the external interference signal is strong enough it will happen with the normal transmission signal stack a plus, resulting in reduced transmission performance even the entire system can not work properly.
 
S/FTP
 
S/FTP structure in addition to the total package of braided foil shield, Twisted Pair Cable is respectively in each pair with a layer of aluminum foil shield to protect the transmission signal does not interfere with each other, so near-end crosstalk attenuation (NEXT)performance dramatically.  NEXT better performance means higher SNR and better transmission quality and faster system output. S/FTP shielded cables NEXT excellent structural performance of other cables (such as non-shielded U/UTP) can not be compared, therefore, ISO11801 on the Cat 7 (600MHz) and Cat 7a  (1000MHz) only provides the S/FTP cable structure, U/UTP cannot meet.
 
10GBase-T make data cable is facing new problems: Alien Crosstalk
 
2006 Copper Gigabit Ethernet applications published the proposed new standard transport protocols 10GBASE-T compared to 1000Base-T, its transmission rate increased 10 times.
 
1000BASE-T copper cabling required parameters (Attenuation, NEXT, Return Loss, etc.) the bandwidth required to reach 1-100MHz, with UTP Cat 5e (Class D) cabling system to meet requirements.
 
10GBASE-T cabling channel requirements of all component parameters have to be up to 500MHz bandwidth, which requires copper to reach at least Cat.6A (Class Ea) or higher level.
 
Along with the development of 10GBASE-T, external noise problems become more evident, resulting in a specification for external noise to be used to assess in the same bundle of cables, the interaction between different cables. This is what we call Alien Crosstalk. Alien Crosstalk will increase with the increase of frequency.
 
Worse, 10GBASE-T confronted with external noise, will not be able to "adaptive" to lower the rate at which the network may be subsequently face paralysis.
 
Therefore, to support 10GBASE-T cabling system application, the ability to resist alien crosstalk is vital.
 
. Since 10GBASE-T high transmission frequencies and complex coding method is very sensitive to the external noise.
 
. Shielding system excellent coupling atttenuation performance makes it naturally have to resist alien crosstalk.
 
. The unshielded system against alien crosstalk is usually only on the performance of 0dB.
 
. Shielding system in the design is completely satisfy the application of 10G.
 
The installation of 10GBase-T: U/UTP VS. FTP
 
Unshielded system: As far as possible away from power cable during installation; Different applications (1Gb/s and 10Gb/s) in the same pipeline transmission will cause the external crosstalk.
 
Shielding system: With the power cable can be reduced separation distance; Allow different applications (1 Gb / s and 10 Gb / s) in the same pipeline transmission; Does not need additional external crosstalk test field.
 
The separation distance between the data cable and power cable
 

In EN50174 standard defines the content of different coupling attenuation value level of data cable, respectively, from A (low coupling attenuation, worse) to D (high coupling attenuation, good) four levels.

Table 1- Classification of information technology cables

 
Installers need to know which cable separated levels to determine the choice of the data requirements of the standard cable with power cable between the minimum separation distance. Data cable coupling attenuation higher the value and power cables minimum separation distance between the smaller.
 
Please refer to the following three examples, screenshots from Nexans Toolkit.
 
Example 1: U/UTP (Class B - Coupling Attenuation >/= 40dB) -> 225mm
 
 
Example 2: F/UTP (Class C - Coupling Attenuation >/= 55dB)-> 114mm
 
 
Example 3: S/FTP (Class D - Coupling Attenuation >/= 80dB)-> 24mm
 
Relative to the shielded cable, the unshielded (U/UTP) separation distance between cable and power cable to further. In the implementation of the project, if need the data cable and power cable isolation far distance, we need a bigger size pipe/bridge, or even additional bridge, doing this will no doubt have higher cost, sometimes limited to the bridge installation space. To make matters worse, these additional requirements often neglected or ignored, resulting in network system is the key point of interference.
 
Grounding
 
For shielded, unshielded systems and Fiber Optic Cables, all need to implement protective grounding. Because of the need to consider personal and equipment safety, therefore no matter adopt what kind of cabling system, the metal part of the system must be grounded.
 
For the shielding system, also need to implement the functional ground. Grounded shielding system functions with respect to the implementation of non-shielded systems only difference is that when you install the module connector and the cable shielding mask area area connected.
 
Overview
 
Shielding system relative to the unshielded system has been greatly improved EMC performance. For Gigabit Ethernet applications, shielding against external interference effects is essential, and shielded cabling system had to meet the standards in the design of anti-alien crosstalk (A-XT) requirements, can effectively prevent the cable from the adjacent between the external crosstalk.


2013 年 8 月 20 日  星期二   晴天


The Core Technology Of WIRING 分類: 未分類

1. High-precision Optical Time Domain Reflectometer(ODTR)

OTDR technology through sending a test signal in the measured line while monitoring signal in the line of reflection phase and intensity. If the signal through the cable encounter mutation of an impedance, part or all of the signals will be reflected back, the reflected signal delay, size and polarity indicate the discontinuity position and feature of the special impedance in the cable.

2. Split Pairs

UTP(Unshielded Twisted Pair) cable is two insulated Copper Wire Cable twisted together to each other by a certain density, which reduces the degree of signal interference, each wire in the transmission of radiation waves are offset by radio waves from the other line.

The so-called split pairs is the original two pairs are opened and yet again to reform a new pair. Because when this failure occurs, the end-to-end connectivity is good, so use a multimeter or hand tool such tools can not check it out. Only with a dedicated cable tester to check it out. Since crosstalk on the related lines of no kink, so online pairs when signal through will produce a high near-end crosstalk (NEXT).

Split pairs normally also be used, but often crosstalk index is large, only to run in the 10M application, can not achieve the 100M application.

3. The Standard Twisted Pair Terminations

Twisted pair eight lines are inserted into the plug (or termination) according to the standard. There are two termination criteria: EIA/TIA T568A/T568B, no essential difference between them, but the difference between color. The natural problem of termination is to ensure that: 1, 2 are a pair; 3, 6 are a pair; 4, 5 are a pair; 7, 8 are a pair. Note: Do not one cable end with T568A, but the other end with T568B. The mix use of T568A/T568B is a special connection method of cross connection. Projects more use T568B wire method.

In Ethernet, Pin1, Pin2 is a twisted pair responsible for network data transmission, Pin3, pin6 is a twisted pair responsible for network data reception, so 1, 2 a pair, 3, 6 a pair, 4, 5 a pair, 7, 8 a pair, it is a must, and not 1, 2, 3, 4, 5, 6, 7, 8 pairs, so called split pairs, will lead to serious signal leakage.

4. Wire Map

Ware Map: This is to confirm the integrity of link connection, mainly to check each pair of 8-core Twisted Pair Cable whether meets the required standards EIA/TIA- 568A/568B, whether the wire at both ends of cable is matching. If wrong, there are five cases include open circuit, short circuit, crossed pairs, reversed pair and split pairs.

● Open circuit: refers to the phenomenon of line off, generally due to bad crystal head cable connection, common with the cable test equipment can locate the fault point.

● Short circuit: refers to one or more wires touch each other in a metal core, resulting in a short circuit.

● Crossed pairs: refers to wire at both ends error in the routing process, which is one end with 568A and the other end with the 568B, usually such wire method used in network equipments level, or network cards connection, but as a general wiring to say, as long as the two ends of the wire method consistent, as for the module wire method can refer to the color above.

● Reversed pairs: this error is due to both ends of a pair line connected to the positive and negative error, is generally believed that the odd line number for the positive electrode, the even line as the negative electrode, for example, 568B Pin1 orange white lines to the first pair of positive, Pin2 Orange Line is negative, it can form a direct current loop, reverse connection is positive and negative confused in the same pair line.

● Split pairs: this is one of the common wire error, which is not strictly comply with wire standard, it is specified in the standard that 1, 2 is the first pair, 3, 6, is the second pair, if 3, 4 into the second pair will cause large signal leakage, which produces NEXT (near end crosstalk), this will cause the user’s Internet difficulties or indirect interrupts, especially in the 1000Mbps network it is particularly obvious.



2013 年 8 月 19 日  星期一   晴天


Fiber Connector And Adapter Panel For Optical Links Together 分類: 未分類

Fiber optic connector is used for the connection of optical fibers or fiber optic cables. The Optical Connector provide a mechanical connection for the two fiber cables and align both cores precisely.

There have been over 100 connectors developed over the years, but a select few have stood the test of time and beat out their competition. Fiber Optic Connectors according to the different transmission media can be divided into common silicon-based optical fiber single-mode and multimode connectors, as well as other issues such as plastic and as the transmission medium of optical fiber connector; connector structure can be divided into: FC SC, ST, LC, D4, DIN, MU, the MT and so on in various forms, but SC and LC connectors are the most common types of connectors on the market. ST connector is the most popular connector for multimode networks. Different connectors are required for multimode and single-mode fibers.

In addition to connectors that tie two fiber-optic lines together, there are also Metal Adapter Panel (or fiber adapter plates) that can be used to connect multiple fiber-optic lineself. It enables you to make quick and easy fiber patch panel connections as they can snap into the enclosures easily. In a device such as this, connections can be made between any of the lines plugged into the panel. Though a single adapter panel can usually only hold a dozen or so cables, the panels can also be spliced together, allowing hundreds or thousands of connections to be made.

Specify optical fiber adapter plates for ST-, FC-, SC-, MT-RJ- or LC-type connections. Adapter plates are compatible with all wall and rack mount optical fiber enclosures and available in 6 simplex and duplex, 8 simplex and duplex and 6 quad configurations with fiber counts of up to 24 per adapter plate. They mount easily by means of plunger locks (“pushpins”). ST, FC, SC and LC connec-tor plates can be equipped with 62.5-μm and 50-μm adapters suitable for multimode applications or a sisingle modenly version is available with adapters outfitted with zirconia ceramic sleeves. Our SC and LC 10G multimode laser optimized adapter uses zirconia ceramic sleeves.

Series Features

Available in 6-, 8-, and 12-port fiber configurations,
Panel options available include ST, SC, LC and others,
High density applications can be reached through Dual and Quad LC applications,
Composite, Metal, or Ceramic sleeve options available,
Blank panels are available for use as dust covers,
Plates are available for mounting Bezel style jacks creating a mixed media environment.

In order to customize wall mount or rack mount fiber optic enclosures, FiberStore offers a wide selection of panels with various FC Adapter including ST, SC, MTRJ and LC. All modular adapter panels are assembled with industry standard adapters. FiberStore fiber adapter panels/plates can come with various fiber adapters, such as LC/SC/ST/FC/MT-RJ, E-2000 fiber optic adapters, compatible with simplex or duplex and meet TIA/EIA-568-B.3 requirements. Our adapter plates include phosphor bronze or zirconia ceramic split sleeves to fit specific network requirements. LC and SC adapter housing colors follow the TIA/EIA-568-C.3 suggested color identification scheme. Multimedia modular panels allow customization of installation for applications requiring integration of fiber optic and copper cables. Blank fiber adapter panels reserve fiber adapter panel space for future use.



2013 年 8 月 15 日  星期四   晴天


Cable Testing With Fluke Cable Tester 分類: 未分類

No matter installing new cable, or troubleshooting the existing cable, cable testing plays an essential role in the process. Common tests for datacom cabling include length, wiremap, attenuation, NEXT, DC loop resistance, and return loss. When doing cable testing must with the Fiber Tester, and the Fluke NetTool is popular.

As networks evolve, so do the requirements of the cabling infrastructure to support them. New standards are continuously being developed to provide guidelines for cabling professionals when installing, testing, troubleshooting, and certifying either copper and fiber. Whether it’s 10BASE-T, 100BASE-TX or 1000BASE-T, there are specific requirements and potential pitfalls in implementing these technologies. And 10GBASE-T, it becomes even more critical to keep current with the latest proliferations in cabling and cable testing.

Cable testing provides a level of assurance that the installed cabling links provide the desired transmission capability to support the data communication desired by the users. Cable test instruments are designed with a variety of focused features for particular field tasks. They vary in price, performance, and application.

For example, there are typically two types of tools for checking network connectivity: the network tester tool and the Fluke tester. Sometimes an engineer will carry a noise generator which not only checks ethernet networks but also telephone lines. Network tester tool is the network checker which plugs directly into the line and reads out what line is connected on that drop, or if there is no signal there. This can also be done with a laptop computer, but it is easier to carry a network tester, since it is far smaller. The Fluke tester will read all four twisted pairs of a cable right from the drop at the workstation all the way back to the server room and will show exactly which pairs are good and if any are crossed or open. The engineer can put a noise on the line and trace it back to the complex loom of cables in the server room all arriving in the same area at the main switch or patch panel.

Verification test tools perform basic continuity functions, they assure that all wires in a cabling link are connected to the proper termination points and not to any other conductors. In twisted pair cabling, it is critical to maintain the proper pairing of the wires. Better verification test tools also verify wire pairing and detect installation defects like “split pairs”. Verification test tools may also assist in troubleshooting by providing a toner to locate a cabling link. Verification tools sometimes include additional features such as an OTDR Price to determine length of a cable or distance to a break or short circuit. These test tools do not provide any information on bandwidth or suitability for high-speed data communication.