Tag Archives: Ribbon Cable

The Anatomy of MPO Trunk Cable Assembly

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New cable designs are being developed to address the specific needs of connectorized cable assemblies. There are various industry-standard tests that evaluate the mechanical and environmental performance of cables and another set of standard tests for connectorized assemblies. In many cases, there are choices made in the cable design parameters, which may affect the cable assembly process, without due consideration of the complications that might be added to the assembly processes. Over the past few years, manufacturers have sought to co-develop new cables and the associated cable assemblies, which improve both the performance and processing of the assemblies. Here we report the development of innovative new trunk cables and associated cable assemblies.

Fiber optic cables are designed to meet rigorous standards for cable performance. These requirements include mechanical and environmental testing such as long length tensile testing and temperature cycling. A successful design is judged by how well it meets these requirements. The cable manufacturer then sells the cable to an assembly manufacturer that will furcate and connectorize the fibers from the cable to make a cable assembly.The furcation removes the outer jacket of the cable and prepares the fibers to receive a connector. Additionally, the furcation terminates the cable strength members and must isolate fiber strain in the cable from the connector. The furcation process may include adding a protective furcation leg over the fibers to provide protection between the end of the cable jacket and the connector. The design of the cable has a significant impact on the design and complexity of the furcation. The objective of this effort was to re-design the cable assembly to improve furcation processing and add customer preferred features to the trunk cable assembly.

Traditional high fiber count trunk cable assemblies have been made with fire retardant ribbon cables. These cables have the advantage that the fiber optic ribbons easily mate to the 12-fiber MPO connectors. The MPO connectors are preferred by customers because they allow quick and easy connection of the trunk cables to the MPO/LC breakout modules in a patch panel. However, the rectangular furcation legs have significant preferential bending which may be bothersome during installation. The ribbon trunk cables have several characteristics that may beaggravating during cable assembly and installation. The cables have a ribbon stack contained within a hard plastic buffer tube that is surrounded by tensile yarn and an outer jacket. This design provides a robust cable but makes a fairly stiff cable with a large bend radius,which may be difficult to route during installation. Furthermore, the cable design drives the requirement for a large furcation plug and pulling grip that requires more space for pulling the cable in during installation.

ribbon cable

Cables utilized in preterminated assemblies come in many varieties, but there are some common features to all cables. Cables consist of optical fibers, strength members and an outer protective jacket. The cable designs considered in this work were ribbon cables and non-ribbon cables. Each design used 250 µm colored optical fibers. The ribbon cables had the fibers grouped in a linear array with 12 fibers per ribbon. The unitized cables consist of individual units that contain 12 fibers and aramid yarn. One benefit of using ribbon cable is that the installation of multi-fiber connector is simplified because it is not necessary to group the fibers in such an array to install them into the MPO connector. One detriment of the ribbon cable design is that it necessitates rectangular legs to protect the ribbon in the transition from the furcation to the connector. An advantage of unitized cables is that they enable the use of round furcation legs or, with properly designed cable and furcation, the use of the subunits as the legs themselves. Now the following is the introduction of 12-fiber and 24-fiber trunk cable Assemblies.

trunk cable

MPO Trunk Assemblies are pre-terminated 12-fiber and 24-fiber cable assemblies. The unique design of the MPO Connector allows for rapid gender and polarity change in the field, in support of standards-compliant cable plant migration from 10G cassette-based systems to 40G MPO connector-based parallel optics cable plant. These trunk cable assemblies optimize cable routing requirements to ensure efficient use of pathway space and significantly reduce installation time and cost. All small diameter trunk cable assemblies are factory terminated and tested to deliver verified optical performance and reliability for improved network integrity. 10Gig versions provide 10 Gb/s network performance up to 300 meters for OM3 and up to 550 meters for OM4 per IEEE 802.3ae 10 GbE standard while maintaining compatibility with legacy systems.

10G fiber backbone or permanent link when mated to MTP Cassettes or fiber adapter panels paired with MPO to LC breakout harnesses. Method A and Method B TIA 568-C compliant for 40G parallel optics multimode applications. Allows system designers to tailor configuration, reach and breakout construction to application requirements; to minimize waste, optimize cable management, speed deployment, improve flexibility and manageability for lower installation costs. Small diameter trunk cable assemblies use 30 – 40% less space which is ideal for high cable density applications.

Guide To Choose The Best Fiber Optic Cable Suits Your Application

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Fiber optic cable is favored for today’s high-speed data communications because it eliminates the problems of twisted-pair cable, such as near-end crosstalk (NEXT), electromagnetic interference (EMI), and security breaches. Fibre Optic Cable is the preferred option in the interconnecting links between floors or buildings, is the backbone of any structured cabling solution. While, making the right decisions when it comes to Data Network cabling is difficult as it can make a huge difference in the ability of your network to reliably support current and future requirements. There are many factors to consider and today I will guide you through the many options available and find the best one suits your application.

1. Multimode Fiber Cable Or Single-mode Fiber Cable

There are two basic types of fiber: mulitimode and single-mode. Both types consist of two basic components: the core and the cladding which traps the light in the core.

Multimode fiber cable

Multimode fiber, as the name suggests, permits the signal to travel in multiple modes, or pathways, along the inside of the glass strand or core. It is available with fiber core diameters of 62.5 and a slightly smaller 50 microns. The problem with multimode fiber optics is that long cable runs in multiple paths may lead to signal distortion. This can result in incomplete and unclear data transmission.

Applications covering short distances can use multimode fiber optic network cable. Ideal uses for such kinds of cables are within data center connections. Multimode cables are economical choices for such applications. There are various performance levels within the multimode fiber optic cable such as OM3 cable for distances within 300 m, OM4 cable supports Gigabit Ethernet distances within 550m and 10G applications.

Single-mode fiber cable

Single-mode fiber cables offer a higher transmission rate. These cables contain a tiny core that measures about five to ten microns. These tiny cores have the capacity to eliminate distortion and produce the highest transmission speeds. Single-mode fiber generally has a core that is 8.3 microns in diameter. Singlemode fiber requires laser technology for sending and receiving data. Although a laser is used, light in a single-mode fiber also refracts off the fiber cladding. The presence of high intensity lasers helps transfer data across large distances. Singlemode has the ability to carry a signal for miles.

Single mode is used for long haul or extreme bandwidth applications, gives you a higher transmission rate and up to 50 times more distance than multimode, but it also costs more. The small core and its single lightwave virtually eliminate any distortion that could result from overlapping light pulses, providing the least signal attenuation and highest transmission speeds of any fiber cable type.

The best choice to choose multimode optical cable when the transmission distance is less than 2km. In the other sides, use single-mode optical cable when the transmission is more than 2km. Although the core sizes of multimode and singlemode fiber differ, after the cladding and another layer for durability are applied, both fiber types end up with an outer diameter of about 250 microns. This makes it both more robust and easier to work with.

2. Indoor Cable Or Outdoor Cable

The major difference between indoor and outdoor cables is water blocking. Any conduit is someday likely to get moisture in it. Outdoor cables are designed to protect the fibers from years of exposure to moisture.

Indoor Cables

Indoor cables are what we call “tight-buffered” cables, where the glass fiber has a primary coating and secondary buffer coatings that enlarge each fiber to 900 microns—about 1mm or 1/25-inch—to make the fiber easier to work with. Indoor cables are flexible, and tough, containing multiple Tight Buffered or Unit Cord fibers.

Types Of Indoor cables available

indoor cables

Simplex and Zip Cord: Simplex Fiber Optic Cables are one fiber, 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, but zipcord can also be used for desktop connections. They are commonly used in patch cord and backplane applications. Additionally, they can be utilized for desktop connections. These cables only have one fiber and are generally used indoors.

Distribution cables: They 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. The distribution cable is smaller and used in dry and short conduit runs, plenum and riser applications, is the most popular cable for indoor use.

Breakout cables: They are made of several simplex cables bundled together inside a common jacket for convenience in pulling and ruggedness. This is a strong, rugged design, but is larger and more expensive than the distribution cables. It is suitable for conduit runs, riser and plenum applications, is ideal for industrial applications where ruggedness is important or in a location where only one or two pieces of equipment (such as local hubs) need to be connected.

Outdoor Cables

Optical fiber in outdoor applications requires more protection from water ingress, vermin, and other conditions encountered underground. Outdoor cables also need increased strength for greater pulling distances. Buyers should know the potential hazards that the cables will face, for example, if the cables will be exposed to chemicals or extreme temperatures.

Loose Tube cables: These cables are composed of several fibers together inside a small plastic tube, which are in turn wound around a central strength member and jacketed, providing a small, high fiber count cable. This type of cable is ideal for outside plant trunking applications, as it can be made with loose tubes filled with gel or water absorbent powder to prevent harm to the fibers from water. Since the fibers have only a thin buffer coating, they must be carefully handled and protected to prevent damage. It can be used in conduits, strung overhead or buried directly into the ground.

Ribbon Cable: This cable offers the highest packing density, since all the fibers are laid out in rows, typically of 12 fibers, and laid on top of each other. This way 144 fibers only has a cross section of about 1/4 inch or 6mm! Some cable designs use a “slotted core” with up to 6 of these 144 fiber ribbon assemblies for 864 fibers in one cable! Since it’s outside plant cable, it’s gel-filled for water blocking.

Armored Cable: Cable installed by direct burial in areas where rodents are a problem usually have metal armored between two jackets to prevent rodent penetration. This means the cable is conductive, so it must be grounded properly. You’d better choose armored fiber cable when use cable directly buried outdoor.

Aerial Cable: They can be lashed to a messenger or another cable (common in CATV) or have metal or aramid strength members to make them self supporting. Aerial cables are for outside installation on poles.

The table below summarizes the choices, applications and advantages of each.

Cable Type Application Advantages
Distribution Premises Small size for lots of fibers, inexpensive
Breakout Premises Rugged, easy to terminate, no hardware needed
Loose Tube Outside Plant Rugged, gel or dry water-blocking
Armored Outside Plant Prevents rodent damage
Ribbon Outside Plant Highest fiber count for small size

All cables share some common characteristics. For example, they all include various plastic coatings to protect the fiber, from the buffer coating on the fiber itself to the outside jacket. All also include some strength members for pulling the cable without harming the fibers. Outdoor fiber optic cable has moisture protection, either a gel filling or a dry powder or tape. Direct-buried cables may have a layer of metal armor to prevent damage from rodents. It is advisable that you should customize your cable to make it suitable to your application when the quantity of fiber optic cables is large and also for the cost-effective reasons. Knowing basic information about fiber optic cables make choosing the right one for the project a lot easier. It is always beneficial to konw more about fiber optic cables.