Tight Buffer Cable VS Loose Tube Cable

You may familiar with bulk fiber optic cable, but how much do you know the differences between tight buffer fiber and loose tube cable? This article will focus on tight buffer vs loose tube cable.

tight buffer vs loose tube cable

Tight Buffer vs Loose Tube Cable Design

Tight buffer or tight tube cable designs are typically used for ISP applications. Each fiber is coated with a buffer coating, usually with an outside diameter of 900m.

Loose buffer or loose tube cables mean that the fibers are placed loosely within a plastic tube whose inner diameter considerably larger than the fiber itself. Usually 6 to 12 fibers are placed within a single tube. The interior of the plastic tube is usually filled with a gel material that protects the fibers from moisture and physical stresses that may be experienced by the overall cable. Loose buffer designs are used for OSP applications such as underground installations, lashed or self-supporting aerial installations, and other OSP applications.

Advantages of Tight Buffer vs Loose Tube Cable

Each construction has inherent advantages. The loose buffer tube offers lower cable attenuation from microbending in any given fiber, plus a high level of isolation from external forces. Under continuous mechanical stress, the loose tube permits more stable transmission characteristics. The tight buffer construction permits smaller, lighter weight designs for similar fiber configuration, and generally yields a more flexible, crush resistant cable.

The other fiber protection technique, tight buffer, uses a direct extrusion of plastic over the basic fiber coating. Tight buffer constructions are able to withstand much greater crush and impact forces without fiber breakage.

The tight buffer design, however, results in lower isolation for the fiber from the stresses of temperature variation. While relatively more flexible than loose buffer, if the tight buffer is deployed with sharp bends or twists, optical losses are likely to exceed nominal specifications due to microbending.

Tensile Loading

Cable tensile load ratings, also called cable pulling tensions or pulling forces, are specified under short-term and long-term conditions. The short-term condition represents a cable during installation and it is not recommended that this tension is exceeded. The long-term condition represents an installed cable subjected to a permanent load for the life of the cable. Typical loose-tube cable designs have a short-term (during installation) tensile rating of 600 pounds (2700 N) and a long-term (post installation) tensile rating of 200 pounds (890 N).

Conclusion

Tight buffer vs loose tube cable, each has its own advantages and uses. Nowadays there are many big brands fiber optic cable manufacturers provide tight buffer cables and loose tube cables. FS.COM, also offers a wide range of bulk fiber optic cables, including cables from corning and cables for different applications, bulk fiber optic cable can be made in a variety of lengths and configurations to meet your needs. For more details, please visit FS.COM.

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Size and Weight Advantages of Fiber Optic Cable over Copper Cable

Size and weight factors are always needed to be taken into consideration when preparing for a cable plant installation. Fiber optic cables are now running existing conduits or raceways that are partially or almost completely filled with copper cable. This is another area where small fiber optic cable has advantages over copper cable. In this article, we will do a comparison and try to determine the reduced-size and weight advantages of fiber optic cable that over copper cable.

advantages of fiber optic cable

Advantages of Fiber Optic Cable

As we already know, a coated optical fiber is typically 250um in diameter. We learn that fiber optic ribbon cable sandwich up to 12 coated optical fibers between two layers of Mylar tape. Twelve of these ribbons stacked on top of each other form a cube roughly 3mm by 3mm. This cube can be placed inside a buffer and surrounded by a strength member and jacket to form a cable. The overall diameter of this cable would be only slightly larger than an RG6 coaxial cable or a bundle of four Category 5e cable.

So how large would a copper cable have to be to offer the same performance as the 144 optical fiber ribbon cable? That would depend on transmission distance and the optical fiber data rate. Take Category 5E cable as an example, let’s place a bundle of Category 5e cables up against the 144 optical fiber ribbon cable operating at a modest 2.5Gbps data rate over a distance of just 100m.

A Cat5e cable contains four conductor pairs and as defined in ANSI/TIA-568-B.2 is 0.25” in diameter. Each pair is capable of a 100MHz transmission over 100m. 100MHz transmission carries 200 million symbols per second. If each symbol is a bit, the 100MHz Category 5e cable is capable of a 200Mbps transmission rate. When the performance of each pair is combined, a single Category 5 cable is capable of an 800Mbps transmission rate over a distance of 100m

Now let’s see how many Category 5e cables will be required to provide the same performance as the 144 optical fiber ribbon cable. The 144 optical fiber ribbon cable has a combined data transmission rate of 360Gbps. When we divide 360Gbps by 800Mbps, we see that 450 Category 5e cables are required to equal the performance of this modest fiber-optic system.

When 450 Category 5e cables are bundled together, they are roughly 5.3 inches in diameter. As noted earlier in this chapter, the 144 optical fiber ribbon cable is approximately the size of four Category 5e cables bundled together. The Category 5e bundle thus has a volume of roughly 112.5 times greater than the 144 optical fiber ribbon cable. In other words, Category 5e bundles need 112.5 times more space in the conduit than the 144 optical fiber ribbon cable.

This comparison we just made is very conservative. This distance we used was kept very short and the transmission rate for the optical fiber was kept low. We can get even a better appreciation for the cable size reduction fiber optic cable offers if we increase the transmission distance and the data rate.

In this comparison, let’s increase the transmission distance to 1,000m and the data transmission rate to 10Gbps. The bandwidth of a copper cable decreases as distance increases, just as with fiber-optic cables. Because we have increased the transmission distance by a factor of 10, it’s fair to say that the Category 5e cable bandwidth will decrease by a factor of 10 over 1000m.

With a reduction in bandwidth by a factor of 10, we will need ten times more Category 5e cables to equal the old 2.5Gbps performance. In other words, we need 4,500 Category 5e cables bundled together. In this comparison, however, the bandwidth has been increased from 2.5Gbp to 10Gbps. This means we have to quadruple the number of Category 5e cables to meet the ban width requirement. We now need 18,000 Category 5e cables bundled together. Imagine how many cables we would need if the transmission distance increased to 80,000m. We would need whopping 1,440,000 Category 5e cables bundled together.

These comparisons vividly illustrate the size advantages of fiber optic cable that has over copper per cables. The advantage becomes even more apparent as distances increase. The enormous capacity of such as small cable is exactly what is needed to install high-bandwidth systems in buildings where the conduits and raceways are almost fully populated with copper cables.

Now we have calculated the size advantages of fiber optic cable over Cat5e cable. Let’s look at the weight advantages of fiber optic cable. It is pretty easy to see that thousands, tens of thousands, or millions of Cat5e cable bundled together will outweigh a ribbon fiber optic cable roughly one half of an inch in diameter. It’s difficult to state exactly how much less a fiber optic cable would weigh than a copper cable performing the same job – these are just too many variables in transmission distance and data rate. However, it’s not difficult to imagine the weight savings that fiber-optic cables offer over copper cables. These weight savings are being employed in commercial aircraft, military aircraft, and the automotive industries, just to mention a few.

Conclusion

From the above, we have learned the size and weight advantages of fibre optic cable. FS, a reliable provider of networking equipment, offers a comprehensive line of fiber optic cables and Ethernet cables. Any queation about cabling, please contact us via sales@fs.com.

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Common Fiber Optic Cable Types Review

Fiber optic cables has become a standard component in most contemporary cable infrastructures. As used for optical fibers varies, fibre optic cable manufacturers have produced cables to meet specific needs, and it is likely that moe will be created as future applications emerge. Bear in mind that different cable arrangements are variations on theme. Different combinations of buffer types, strength members, and jackets can be used to create cables to meet the needs of a wide of industries and uses.

Let’s go over several common types of fiber optic cables

Cordage

The simplest types of cables are actually called cordage, and are used in connections to equipment and patch panels. They are typically made into patch cords or jumpers. The major difference between cordage and cables is that cordage only has one optical-fiber/buffer combination in a jacket, while cables may have multiple optical fibers inside a jacket or sheath.

The two common types of cordage are simplex and duplex.

simplex cordage

Simplex cordage consist of a single optical fiber with a tight buffer, and aramid yarn strength member, and a jacket. Simplex cordage gets its name from the fact that, because it is a single fiber, which is typically used for one-way, or simplex, transmission, although bidirectional communications are possible using a simple fiber.

Duplex cordage, also known as zipcord, is similar in appearance to household electrical cords. It is a convenient way to combine two simplex cords to achieve duplex, or two-way, transmissions without individual cords getting tangled or switched around accidentally.

duplex cordage

Distribution cable

Distribution cables is need when it requires to run a large number of optical fibers through a building. Distribution cable consist of multiple tight-buffered fibers bundles in a jacket with a strength member. These cables may also feature a dielectric central member to increase tensile strength, resist bending, and prevent the cable from being kinked during installations.

These cable are ideal for inter-building routing. Depending on the jacket type hey may be routed through plenum areas or riser shafts to telecommunications rooms, wiring closet, and workstations.

The tight-buffered optical fibers are not meant to be handled much beyond the initial installation, since they do not include a strength member and jacket. Distribution cables may carry up to 144 individual tight-buffered optical fibers, many of which may not be used immediately but allow for future expansion.

Armored cable

Armored fiber optic cable has two jackets. The inner jacket is surrounded by the armored and the outer jacket or sheath surrounds the armor. This cable can be used for indoor and outdoor applications.

Armored cables are used for outdoor application is typically a loose tube construction designed for direct burial applications. The armor is typically a corrugated steel tape surrounded by an outer polyethylene jacket. This combination of outer jacket and armor protects the optical fibers from gnawing animals and the damage that can occur during direct burial installations.

Armored cable for outdoor applications

Armored cables used for indoor applications may feature tight-buffered or loose-buffered optical fibers, strength members, and an inner jacket. The inner jacket is typically surrounded by a spirally wrapped interlocking metal tape armor. This type of armor is rugged and provides crush resistance. These cable are used in heavy traffic areas and installations that require extra protections, including protection from rodents.

Armored cable for indoor applications

Ribbon Cable

As it name indicate that fiber optic ribbon cable contains fiber ribbons, which are actually coated optical fibers placed side by side, encapsulated in Mylar tape, similar to a miniature version of wire ribbons used in computer wiring. A single ribbon may contain 4, 8, 12 optical fibers. Ribbon cable can be stacked up to 22 high.

Because the ribbon contains only coated optical fibers, this type of cable takes up much less space than individually buffered optical fibers. As a result, ribbon cables are denser than any other cable design. They are ideal for applications where limited space is available, such as in an existing conduit that has very little room left for an additional cable.

Besides, ribbon cables come in two basic arrangements wich is loose tube ribbon cable and jacket ribbon cable.

armored loose tube ribbon cable and jacket ribbon cable

In the loose tube ribbon cable, fiber ribbons are stacked on top of one another inside a loose-buffered tube. This type of arrangement can hold several hundred fibers in close quarters. The buffer, strength members, and cable jacket carry any stain while the fiber ribbons move freely inside the buffer tuber.

The jacket ribbon cable looks like a regular tight-buffered cable, but it is elongated to contain a fiber ribbon. This type of cable typically features a small amount of strength member and a ripcord to tear through the jacket.

Ribbon fiber provides definite size and weight savings, it does require special equipment and training to take advantage of those benefits. Connectors, strippers, cleavers, and fusion splicers must all be tailored to the ribbon fiber. For these reasons, ribbon fiber may not be the best solution in all situations.

Expect the above cables, there are also other fiber optic cable types like Submarine cable for carrying optical fiber underwater; Aerospace cable designed to be installed in aircraft and spacecraft; Aerial cable (figure 8 cable) for aerial installations; Hybrid cable combined multimode and single-mode optical fibers in on cable as well as the composite cable that designed to carry both optical fiber and current-carrying electrical conductors in the same run.

The Selling Price Of Fiber Optic Cable

In general, fiber optics cost from 1 to 5 percent more than standard copper wire and multimode fiber sells at a higher price than single-mode fiber.

Although single-mode fiber is by far the predominant fiber for telecommunications, multimode is used in short-reach applications, including for data centers and some other local area networking deployments, as well as for numerous specialized applications not for telecom, such as medical uses, imaging and some illumination.

Multimode is not cheaper than single-mode fiber. However, the inexpensive LEDs or vertical-cavity surface-emitting lasers (VCSELs) and detectors used to power it are generally less expensive than its single-mode fiber counterparts. The real growth potential is in data centers using VCSELs with multimode fiber. Optical component vendors that can use VCSELs to carry signals in duplex or multistrand multimode fibers may find a market in local area networks or the growing number of data centers throughout the world. Short-range links would appear to be perfect for multimode fibers.

Although konw multimode fiber is more expensive than single mode fiber, what are the other factors deciding the fiber optic cable price?

Fiber optic cable prices are different based on the different cable types, even for the same structure fiber optic cables, the prices may be different because of the different fiber counts, jackettypes, lengths, etc.

The cable design influences the cost of a fiber optic cable. A simple duct cable will be less priced than a direct buried cable, which needs extra protection to meet additional mechanical and environmental safety when the cable is used for direct buried application. A self-supporting type aerial cable may be more expensive than a duct and direct buried type cables. The number of sheaths affects the cost. The more the number of sheathing layers, the higher the cost of cable will be. Process cost and material cost increases drastically proportional to the number of sheathing layers.

It is not always the construction of a cable that decides the cost of a fiber optic cable. The quantity required and delivery also plays major role in the costing of a fiber optic cable. A more quantity, cable manufacturers will offer a cheaper price. When buying a fiber optic cable from fiber optic cable manufacturer, most probably if we approach a cable manufacturer with a requirement of fiber optic cable, they will ask the quantity and delivery time at first apart from the construction requirements.

Fiber optic cable prices from different fiber optic cable manufacturers are also not same, sometimes they may be quite different, even you are asking about the same structure cable, this may be because of the quality, but brand names may also affect the fiber cable prices.

As you know, Corning developed the first commercial optical fiber in 1970. Corning and OFS remain the No. 1 and No. 2 fiber optic cable makers in the world currently. Corning and OFS almost control every aspect of the optical fiber-making process, including extruding the glass from draw towers, doping it, cooling it, stringing it, testing it, marking it, and then either cabling it or shipping it to other cablers.

Another hidden factor influences fiber optic cable price is the market. If the demand is more and competitors are less, the price will be naturally higher.

FAQs Before Buying Fiber Optic Cable

Fiber optic cable is a large, long-distance optical signal transmission unit, by means of which we can spread out the various optical signals with low attenuation rate to meet signals transmission needs between different fields. There are more than 15.000 varieties of fiber optic cables in the telecommunication field. Choosing the right fiber optic cable is extremely important for any installation. Purpose of the cable is to protect the fibers during installation and the service lifetime. This article is written to address your concerns regarding what types of fibers do you need, where they will be installed, and where to buy fiber optic cable.

fiber optic cable

What Types of Optical Fiber Should I Choose and How Many Fibers?

It may be familiar for you that optical fibers are divided into two different mode which is multimode and single mode.

Single mode fiber has a core that is 8.3 microns in diameter. Single-mode fiber requires laser technology for sending and receiving data. With a laser used, light in a single mode fiber also refracts off the fiber cladding. Single-mode has the ability to carry a signal for mile, making it ideal for telephone and cable television on providers.

Multimode fiber, as the name suggests, permits the signals to travel in multiple modes, or pathways, along the insides of the glass strand or core. It is available with fiber core diameters of 62.5 and a slightly smaller 50 micron. 62.5 micron multimode is referred to as OM1. 50-micron fiber is referred to as OM2, OM3, and the recently added OM4. OM4 has greater bandwidth than OM3 and OM3 has greater bandwidth than OM2.

While single mode fiber has a core that is 8.3 microns in diameter. Single-mode fiber requires laser technology for sending and receiving data. With a laser used, light in a single-mode fiber also refracts off the fiber cladding. Single-mode has the ability to carry a signal for mile, making it ideal for telephone and cable television on providers. 50-micron OM3 fiber is designed to accommodate 10 Gigabit Ethernet up to 300 meters, and OM4 can accommodate it up to 550 meters. Therefore, OM3 and OM4 fiber are always chosen over the other glass types. In fact, nearly 80% of 50-micro fiber sold is OM3 or OM4

Except for the fiber mode, the number of fibers is necessary to know. Usually, unless you are making patch cords or hooking up a simple link with two fiber, it is highly recommended that you include a number of spare fibers. Corporate network backbones are often 48 fibers or more. Most backbone cables are hybrids – a mix of 62.5/125 multimode fiber for today’s networks and single-mode fiber for future networks. If the slowest network planned today is as gigabit speeds, it might even be better to use the new 50/125 multimode fiber optimized for the laser sources used in gigabit networks.

Where to Install the Fiber Optic Cable? Indoor, Outdoor or Both?

Outdoor cables are designed to protect the fibers from years of exposure to moisture. Until recently, your only choice for outdoor cables was loose-tube, gel-filled cables. But now you can buy dry water-blocked cables similar to indoor designs that are easy to terminate without breakout kits, saving incredible amounts of time. In a campus environment, you can even get cables with two jackets: an outer PE jacket that withstands moisture and an inner PVC jacket that is UL-rated for fire retardancy. You can bring the cable into a building, strip off the PE jacket and run it anywhere, while normal outdoor cables are limited to 50 feet inside the building.

Indoor cables are what we called “tight-buffered” cables, where the glass fiber has a primary coating and secondary buffer coatings that enlarge each fiber to 900 microns – about 1 mm or 1/25- inch- to make the fiber easier to work with. These cables can be directly terminated.

The most popular cable for indoor use is distribution cable, which has a number of 900-micron buffered, color-coded fibers inside a single jacket. It’s the smallest and lightest cable, and each fiber is sturdy enough for direct termination. Another choice for indoor use is the breakout cable, which is just a bunch of simplex cables inside a common jacket for convenience in pulling and ruggedness.

Where to Buy Fiber Optic Cable?

Once knowing what kind of fiber optic cables is needed, last but not least is to decide where to buy your required fiber optic cables. In the actual production of fiber optic cable, materials which are wearable, radiation proof and adaptable to temperature is very important. Good core material and the external packages. When buying fiber optic cable, qualification of the fiber optic cable manufacturers should be taken into consideration, choosing qualified and professional manufacturers will ensure you quickly get the problem resolved after the sale.