As the number of fiber optic cable users and installations increases, the need for reliable and cost-effective fiber connections grows ever more critical. Now more than ever, it is vital that you understand the real costs that determine the most financially prudent splicing technique for your business. Nevertheless, cost is not something you can compare at face value.
1. What is Fiber Optic Splicing
Fiber optic splicing is the process of joining two optical fiber cables together. It is an alternative to the more common method of joining fiber cables known as connectorization or termination. It creates a permanent joint between cables. This is in contrast to connectorization where the joint is temporary.
Fiber splicing typically leads to reduced back reflection and light loss when compared to connectorization. This makes it the preferred option when fiber cable runs are too long. It may also be the best option when you are joining cables of different types. For example, four 12-fiber cables joining a 48-fiber cable. All in all, it has widespread use, including repairing buried or accidentally severed fiber optic cables.
2. Cost to Splicing Fiber Optic Cable–Fiber Splicing Methods
Cost to Splicing Fiber Optic Cable–Fusion Splicing
Fusion splicing joins the two cables together via an electric arc. You can do it as single fusion (one fiber at a time) or mass fusion (fusing a dozen fibers in a single action). It is the most popular fiber optic cable splicing technique.
Fusion splicing creates a connection so seamless that the joint is not always detectable by OTDR traces. It provides the most reliable joint. A fusion connection also has the least loss and lowest reflectance. Today’s automated fusion splicers ensure it is difficult to make a mistake, as long as you have cleaved the cables properly.
Almost all single-mode splices use the fusion method. The most common application of single-mode fusion splicing is outside plant installations.
Cost to Splicing Fiber Optic Cable–Mechanical Splicing
Mechanical splicing relies on alignment fixtures to attach the ends of two fiber cables with some glue or gel between them. It creates a somewhat less permanent joint than fusion splicing. There are various types of mechanical splices. These include V-shaped metal clamps and little glass tubes.
Whereas mechanical splicing is best for single-mode fiber. Nevertheless, you will most often apply it to multimode splicing and a temporary restoration. When crimping, apply light pressure on the cable to keep ends together. If possible, use a visual fault locator (VFL) before crimping to optimize the splice.
Cost to Splicing Fiber Optic Cable–Pre-Terminated System
Pre-terminated fiber optic cable systems are factory-terminated via a connector. For this to occur, you must know where the cable will run so you can calculate the length. Using design drawings and CAD systems, the vendor or manufacturer would then build a complete layout of the fiber optic cable system at the factory.
With the complex termination work already done, the remaining fiber network construction is fairly simple. You do not need to possess highly technical fiber laying or joining skills to complete the remaining work quickly. The time you spend on connecting cables reduces from 20 minutes to under 5 minutes. That includes the time you take cleaning connectors.
When planned well, pre-connectorized systems will not increase the number of connection points. That means they reduce the opportunities for reflection and optical loss. Pre-terminated systems are also known as pre-connectorized or prefabricated.
3. Cost and Performance Comparison of Fiber Splicing Techniques
Different fiber optic cable splicing techniques will have different cost and performance scores. Time, equipment, and project scale are the most important drivers of cost and performance. Let’s have a comparison.
Fusion Splicing versus Mechanical Splicing
Cost—Fusion splicing has high upfront costs due to the investment needed to acquire a fusion splicing machine. A good fusion splicer will range from $15,000 to $40,000. Nevertheless, fusion splices are cheap and typically range between $0.50 and $1.50 apiece. Mechanical splicing uses inexpensive equipment. However, the splice hardware is costly at $5 to $30 per mechanical splice. The more splicing you need to do, the less cost-effective mechanical splicing will be.
Therefore, if you are going to make thousands of splices, you are better off going with fusion splicing. However, if you need just a few splices, mechanical splices are your best bet.
Performance—Fusion splices form a continuous connection between two fiber cables. It, therefore, has better performance, lower insertion loss, and lower back reflections. The loss is often less than 0.1 dB thus offering better protection from weak signals and cable failure. This makes it the preferred splicing method for single-mode high-speed fiber cables or CATV networks.
However, fusion splices do not work as well on multimode fiber cables. So for multimode cables, mechanical splicing may be the better option. The exception for multimode is an aerial or underwater application. In this case, fusion splicing’s higher reliability makes it the go-to solution. If you opt for mechanical splicing though, you will have to brace for a higher insertion. This may range between 0.2 dB and 0.75 dB. That is because mechanical splices align and do not actually join the two cables.
Fusion Splicing versus Pre-Terminated System
Cost—The initial cost of fusion splicing is significantly higher than that of pre-terminated systems. Even what you would consider a budget fusion splicer costs about $3,000. However, the splices themselves cost as little as $0.50. This price is far lower than that of a pre-terminated connector.
But pre-terminated systems have cost advantages too. For example, since they do not require any additional hardware and you can terminate them faster. Therefore, pre-terminated systems incur much lower labor costs. Fusion splicing calls for expensive specialized technicians. In contrast, a less trained person can set up a pre-terminated system and would need only plug pieces in position. You can install pre-terminated quickly and cheaply.
Overall, fusion splicing would be the better option in trunk cables where there are as many as 192 fibers to splice. However, in drop locations where you need just one or two splices, pre-terminated systems would make more financial sense. Performance—First, fusion splices have an insertion loss of 0.1 dB or less while pre-terminated system losses are significantly higher at 0.15 dB or lower. Second, fusion splicing equipment is sensitive to the environment. On the other hand, environmental concerns are much less significant for pre-terminated systems. Third, fusion joints are not de-mateable (meaning the connection cannot be undone) while pre-terminated systems are.
One cannot state unequivocally that one method will always cost less and another always cost more. A method may be the least expensive in one setting but the most expensive in another. It depends on the nature of the splicing project at hand. But for help on cable assemblies, get in touch with us.