The electrical utility marketplace is increasingly dependent on high-speed optical networks to aid daily operations. For more than two decades, utilities have used fiber optic media to aid their own personal internal applications. In the past few years, public power companies as well as an occasional electric cooperative have ventured into Fibers in stainless steel tube for the main benefit of their customers as well as the generation of additional revenue streams. In the foreseeable future, new construction and smart grid initiatives promise to expand fiber’s role even farther into electric utility operations. The final point is a reasonably statement considering fiber is available on transmission lines and distribution lines, in generating stations, as well as in substations.
So, when it is a particular that optical fiber is actually a reality from the electric utility industry, then it is necessary for those with responsibility to the control over utility assets to learn a number of the basic categories of optical cable products and where those products best easily fit into the electrical grid. Since most of the fiber used by utilities is deployed inside the outside-plant, among the most common questions center around picking ribbon versus conventional loose tube cable designs and where one solution might be more economically viable compared to other.
Outside plant cables, either aerial or underground, get even closer your home.
Both ribbon cables and conventional loose tube cables are staples from the telecommunications industry and have been around for several years. Both products perform well in harsh outdoor environments, and both are available in numerous configurations, including: all-dielectric, armored, aerial self-supporting, etc. The primary distinction between those two product families is definitely the manner where the individual fibers themselves are packaged and managed in the cable. A ribbon cable has got the individual fibers precisely bonded together within a matrix that could encompass as few as four or up to 24 fibers. Typically, however, these matrixes, or “ribbons” are bonded together in a group of 12 and placed in the tube that holds multiple ribbons. As opposed, a loose tube cable design has between 2 to 24 individual fibers housed in multiple buffer tubes with each fiber detached from your other.
Nearly anyone inside the electric utility industry with any amount of contact with optical fiber products will know about the fundamental structure of loose tube cable. Ribbon cables, alternatively, have enjoyed widespread adoption among regional and long-haul telephony providers but might still be unfamiliar for some in the electric utility space. This unfamiliarity comes with a price since ribbon products will offer a four-fold advantage on loose tube designs in numerous applications:
Ribbon cable may be prepped and spliced considerably more rapidly than loose tube cables. This advantage means less installation time, less installation labor cost, and significantly less emergency restoration time.
Ribbon cables enable a smaller footprint in splice closures and telecommunications room fiber management.
Ribbon cables offer greater packing density in higher fiber counts which enables more potent usage of limited duct space.
Ribbon cables are normally very cost competitive in counts above 96 fibers.
The very first two advantages listed above are byproducts in the mass fusion splicing technology enabled by ribbon cable. A mass fusion splicer can splice each of the fibers inside a ribbon matrix simultaneously. Thus, when a 12 fiber ribbon is utilized, those fibers might be spliced in about 12 seconds with average splice losses of .05 dB. In contrast, the traditional loose tube cable requires each fiber to get spliced individually. So, through comparison, Sheathing line requires 12 splices just to be fully spliced while a 144 fiber count loose tube cable requires a full 144 splices. Along with the time savings, a decreased total number of splices also yields a decrease in the amount of space necessary for splicing. Hence, there is an associated decline in the quantity of space needed to support splicing in closures and in telecommunications room fiber management.
Your reader with experience using ribbon cable might offer two objections at this point. The first objection would be the value of mass fusion splicing equipment, as well as the second objection would be the painful and messy procedure of prepping large fiber count unitube ribbon cables. The 1st objection is definitely overcome just by exploring the current prices of mass fusion splicers. Over the past few years, the fee difference between single-fiber and ribbon-fiber splicing equipment has decreased dramatically. The next objection has been overcome through the creation of all-dry optical cable products. Older ribbon cable products were painful to prep because of the infamous “icky-pick” gel utilized to provide water-blocking. The unitube style of many ribbon cable products translated into an excess of gel along with a general mess for your splicing technician. However, technologies allow both conventional loose tube and ribbon products to fulfill stringent water-blocking standards with no gels whatsoever. This dramatically decreases the cable prep time when splicing both for product families. However, the fundamental design of ribbon cables ensures that the main advantages of all-dry technology yield even more substantial reductions in cable prep time.
For low fiber count applications, ribbon cables possess a significant advantage in splicing costs. The very best point for conversion to ribbon cables typically occurs at 96 to 144 fibers based on the labor rates useful for economic modeling. For the reason that variety of fiber counts, any incremental cost difference between ribbon and loose fiber configurations will probably be offset by savings in splicing costs and installation time. For fiber counts similar to and higher than 144, the carrier would need a compelling reason to not deploy ribbon cables given the reduced value of splicing and very comparable material costs.
Splicing costs vary tremendously depending on the local labor market. Typically, however, single-fiber fusion splicing costs are anywhere between $23 and $35 per-splice with a national level for standard outside-plant cable. For cost comparison purposes, we are going to split the main difference and believe that we need to pay $28 per-splice whenever we sub-contract or outsource single-fiber splicing. If we outsource ribbon-fiber splicing, we will imagine that each 12 fiber ribbon splice costs us $120. Ribbon-splicing costs also vary tremendously according to the local labor market, although the $120 number might be inside the high-average range.
So, in relation to those assumed splice costs, a typical loose-tube cable splice will cost us $4,032.00 on the 144 fiber count (144 single fibers x $28 per-splice) whereas the comparable ribbon cable splicing costs will be $1,440.00 (twelve 12-fiber ribbons x $120 per-splice). This will give us a total savings of $2,592.00 in splicing costs at each splice location. In the event the 144 fiber ribbon cable costs a similar or less than the comparable loose-tube cable, then this case for ribbon in that fiber count and better will be the proverbial “no-brainer.” When a ribbon cable is available that will complete the task in this particular scenario, there is little reason to think about the alternative.
The truth for ribbon versus loose-tube optical cable is less compelling at lower fiber counts. For example, when you use those same per-splice costs in the 96 fiber count scenario, the ribbon cable saves us $1,728.00 at every splice location. However, the financial benefit afforded from the splicing can be offset by higher cable price. Additionally, dexkpky80 amount of splice locations can vary greatly from a single application to the next. Inside a typical utility application, however, 96 fiber configurations represent the point where cable costs and splicing costs often break even when comparing ribbon to loose tube.
The economics of fiber counts notwithstanding, you may still find a couple of places that either ribbon or loose-tube is the preferred option. As an example, it takes four splices to repair a 48 fiber count ribbon cable in comparison to 48 splices to the loose-tube equivalent. On certain critical circuits, therefore, it may be desirable to possess secondary coating line just due to advantages in emergency restoration. Also, ribbon cable items are generally smaller which creates some space-saving advantages in conduit. However, some applications (fiber-to-the-home, for example) require multiple cable access locations where we grab only two to eight fibers from your cable for splicing using mid-sheath access techniques. In those instances, ribbon could be viable with new “splittable” ribbon technologies, but may be less practical for several carriers than conventional loose tube. However, the gel-free technology present in both ribbon and loose-tube is a large labor savings feature in those circumstances. Aerial self-supporting cables (ADSS) still require using some gels, but any utility company installing fiber optic cable in any other application must be leaving the gel-remover back in the shop. “Icky-pick” in conventional ribbon and loose-tube cables is really a relic of the 90’s as well as an accessory for labor hours which may be easily avoided.
To sum it, there exists not a single network design which fits all applications, instead of a single cable that fits all network designs. However, understanding the options and knowing where they fit can significantly impact installation time, labor costs, and emergency restoration time. All the options are field-proven and have been popular for several years. Utilities can leverage the benefits of these different solutions just by remembering precisely what is available, and applying a bit basic math to compare and contrast cable costs, splicing costs, and labor hours.