Breakout or Distribution Cables — Which One to Choose?

Cables with multiple fibers are widely applied to high-density indoor or outdoor installations. Breakout and distribution fiber optic cables are the common used types. However, people may mix them together because they have a similar outer appearance. Actually, the inner structure of these cables are totally different. In this article, some differences between breakout and distribution cables will be discussed.

Cable Structures
Breakout Cable Structure

Breakout cable is also known as fan-out cable. As the following picture shows, breakout cable consists two or more simplex cables bundled around a central strength member. Each fiber has its own jacket and all of the fibers are packaged together inside the same outer jacket. Thus, breakout cable can also be broken out into individual simplex cables for separate use when running through walls of a building. Breakout cable is usually designed with tight buffer and the fiber counts are varied from 2 to 24 fibers.

breakout fiber cable structure

Distribution Cable Structure

Unlike the breakout cable, distribution cable is smaller in size and lighter in weight. Fiber counts of distribution cable can be more intensive than the breakout cable for up to 144 fibers. Many fibers may not be used immediately but can be left for future expansion. Although the distribution cable has a more compact design, the tight-buffered fibers inside the cable are only bundled in a single outer jacket for protection, as shown in the picture below. Yet this has made the distribution cable to be easily handled and stripped for field termination.

distribution fiber cable structure

Cable Types
Types of Breakout Cable

According to different fiber ratings, breakout cable can be divided into breakout riser cable and breakout plenum cable. Breakout riser cable is widely used for vertical riser and general horizontal applications. However, when the cable is needed for ducts, plenums and other spaces with environmental air returns, breakout plenum cable is the better choice.

breakout cable

Types of Distribution Cable

Likewise, distribution cable also has the riser and plenum cable types for riser and plenum spaces deployment. Apart from these types, distribution cable is sometimes equipped with armored jacket for a stronger protection. Armored distribution riser or plenum cable can be applied to harsh premise environments where heavy-duty protection is required.

distribution cable

Cable Applications
Breakout Cable Applications

Breakout cable may end up in communication closets, and users can manually change connections. It is also available to be used for direct connection to the device. Moreover, breakout cable is suitable for short riser or plenum areas and conduit runs, where a very simple cable run is planned to avoid the use of splice box or spliced fiber pigtails. Since breakout cable has a stronger design, it is ideal for industrial applications where ruggedness is needed.

Distribution Cable Applications

Distribution cable is typically used for fast installation and easy termination of outdoor and indoor applications. It supports high performance networks and its single-unit fiber design saves much space. Distribution cable usually ends up at patch panels or communication closets, where they are connected with devices for communications between separate offices or locations. Distribution cable is also used within buildings to provide high-density connectivity for applications of intra-building backbones, routing between telecommunications rooms and connectorized cables in riser and plenum environments.

Conclusion

In summary, it is a convenient solution to use breakout or distribution cables for multi-fiber applications. Certainly, when you have to make a choice between them, you also need to consider the price factor. Breakout cable is generally stronger and larger than the distribution cable, thus the cost will be more expensive. Be sure to have a second thought before making the decision.

Applications for Outside Plant Fiber Optic Cables

Inside plant refers to the cabling running inside a building. Similarly, outside plant is the cabling running outdoors. Outside plant cables are thicker because of more durable insulation jackets. As for fiber optic communication, there are many types of outside plant fiber optic cables. Some have extra protections to prevent corrosion and other elemental interference. Outside plant fiber optics are widely used in telephone networks, CATV, metropolitan networks, utilities and so on. If you want to choose the right outside plant fiber optic cable, its applicable environment is an important factor for consideration. This post will introduce some common outside plant fiber optic cables and typical outdoor application environments.

Several Types of Outside Plant Fiber Optic Cables

Outdoor breakout cable is perfect for rugged applications and installations that require increased performance. It is usually made of several bundled simplex cables wrapped in a common cable jacket. The fungus, water and UV protections and temperature durability are beneficial to its outside applications. Its design of individual fiber reinforcement enables the quick termination to connectors and omits the use of patch panels or boxes. With much less termination work, outdoor breakout cable is more cost-effective when small fiber counts and short distances are required.

breakout-outdoor-cable

Outdoor Loose Tube Cable

Outdoor loose tube cable has the gel-filled design protecting the cable from moisture environment. The gel within the loose-tube construction stops the penetration of water and keeps it away from the fiber. Also, it keeps water from freezing near the fiber at low temperatures which reduces the chance of stress fractures. Fibers are bundled inside a small plastic tube that can protect fibers from outside stresses. Outdoor loose tube cable is often used in conduits, strung overhead or buried directly into the ground.

outdoor-loose-tube-cable

Outdoor Ribbon Cable

Outdoor ribbon cable has high fiber counts and small cable diameter. It contains the most fibers in the smallest cable. These fibers are laid out in rows as ribbons, and ribbons are laid on top of each other. Likewise, it also has gel-filled protection to block outside water. Ribbon cable makes installation much faster and easier since mass fusion splicers can join a ribbon at once.

outdoor-ribbon-cable

Outdoor armored cable is a direct buried type that prevents itself from animal bite. The metal armoring between two jackets effectively prohibits rodent penetration. Outdoor armored cable can be divided into light armored and heavy armored types. The former has the protective plastic jacket with the same durability and longevity of a stainless steel cable with a lighter weight. The latter is wrapped in a wire circle to be applied for underwater regions that near shores and shoals.

outdoor-armored-cable

Outside Cable Plant Applications

Outside cable plant deployment can be implemented in many environments. Above-ground, underground, buried and underwater are the typical applications.

Above-ground Cable Plant

Above-ground cable plant can be exposed to extreme temperatures, and to humidity that varies with the seasons and with daily temperature changes. Cables under such circumstances should be durable to adapt to extreme weathers and water penetration.

Underground Cable Plant

Underground cable plant usually applies cables in underground structures including the utility holes, controlled environmental vaults, ducts and so on. The condition in utility holes and ducts sometimes can be corrosive because of man-made chemicals. Cables with corrosion-proof materials are perfect for this environment.

Buried Cable Plant

Buried cable plant applies cables directly into the soil. Cables can also be exposed to the same corrosive environment as underground plant. But animal bite is an additional problem. Cables for this application should be very tough to endure both chemical corrosion and animal attack.

Underwater Cable Plant

Underwater cable plant are located beneath the surface of water. The water can range from relatively pure to brackish, or to badly contaminated with industrial effluent. Cables for underwater plant are extremely rugged, with fibers in the middle of the cable inside stainless steel tubes and the outside coated with many layers of steel strength members and conductors for powering repeaters.

Conclusion

Unlike indoor cables, outside plant fiber optic cables must be wrapped in different layers to withstand the severe installation conditions. Choosing the right kind of outdoor cable can save you a great deal for long-term maintenance. And your project application is an important aspect that will affect the selection of fiber optic cables.

Fiber Optic Cables For Harsh Environment Applications

Fiber based systems offer apparent advantages over electrical methods in large plants and factories where the harsh environment threatens data reliability and security. Unlike copper cable, fiber optic cabling is resistant to electromagnetic interference (EMI), making it an ideal option for harsh environments involving high voltages or machinery with variable frequency drives, is a safe alternative to traditional wiring.

As you know, fiber optic cable consists of three parts: the core, the cladding, and the coating. The core transmits the light and has a high refractive index. The cladding contains the light within the core because its lower refractive index causes all the light rays to reflect back into the core. This “total internal reflection” or “fiber-optic effect” is the technology’s underlying principle. The coating, usually an acrylate polymer, protects the core/cladding assembly.

Optical fiber is typically made from high-purity silica glass. Plastic fiber of varying configurations is also available. But the attenuation of light energy can approach one thousand times that of glass fiber. The length and integrity of the transmission path and the core/cladding arrangement affect the bandwidth, or the frequency range that the optical fiber transmits. Fiber bandwidth is expressed in megahertz-kilometers (MHz-km).

Depending on the application, the distance involved, and the location, several types of cable configurations and connector types are available. Optical fiber is fragile and must be protected, mostly from mechanical stresses such as bending, crushing, thermal effects, and pulling during installation.

Tight Tube And Loose Tube Cable

A tight-tube (or tight-buffer) design has a PVC coating, which tightly bonds to the fiber, limiting movement. This cable type can have strength members, which you pull through conduit and cable trays. This design, however, has low crush resistance and is susceptible to deformation due to thermal expansion; thus, it is recommended for indoor use only.

A loose-tube design gives a fiber free movement. Each component of the Loose Tube Cables (the sheath or outer coating, the strength member, and the buffer tubes that carry the fibers) has different thermal characteristics. By allowing the fibers and the components surrounding them free movement, deformation is avoided.

Loose-tube construction has much better crush resistance than tight tube because of the buffer-tube protection of the fibers. Loose-tube cables have a strength member, which is used as the pulling member for conduit installation. Loose-tube cables are usually filled with a gel, which surrounds the fibers and increases protection from water. This also improves crash resistance because of the gel’s cushioning effect. You mostly use this cable type for outdoor applications, but you can also use it in harsh industrial environments. A drawback to this type of cable is the difficulty in handling individual fibers. The fiber coating does not have to be as thick as in tight-tube construction; thus, attaching connectors is difficult.

Remember that tight-tube construction does not allow for free movement and provides low protection against mechanical stress. It does, however, have a thick coating for ease of handling. Loose-tube construction, on the other hand, allows free movement and provides a good degree of protection.

Breakout Cable

Breakout cables are a hybrid solution. In a breakout cable, each fiber is treated as a separate unit, complete with a sheath and strength member. This design eliminates the need for a breakout kit, because the sheath lets you attach connectors easily.

Breakout Cable Fiber let fiber subunits move freely, and they protect each fiber by virtue of their thicker coating/strength member arrangement. Each fiber subunit is configured as a tight tube. Breakout cables also come equipped with a separate strength member just like the loose-tube design.

FiberStore harsh environment Fiber Cables is designed and manufactured with specialized components which provide improved performance and protection against damage, breakage, and performance limiting conditions that often exist in harsh environment applications. FiberStore has the resources, expertise, and experience to design, develop, manufacture, install, and maintain a product ideally suited for your exact application.