Fiber optic joints or termination is a necessary process when installing a network. Every network operators who aim to deploy a next-generation fiber network have to determine how to build a flexible, reliable and long-lasting infrastructure at the lowest possible cost. In general, there are mainly two fiber optic termination methods: splices which create a permanent joint between the two fibers, or connectors that mate two fibers to create a temporary joint. When people decide to use either method, many factors should be taken into account. Today’s article will evaluate both methods from the aspect of cost to help you choose the effective termination method.
Weighting the Two Methods
Besides the features of low loss, minimal reflectance and high mechanical strength, fiber optic termination must be compatible to the environment in which they are installed. Before we come to the cost comparison of these two termination methods, let’s firstly have a brief overview.
As it known to all that, splices create a permanent joint between two fibers, so its use is limited to place where cables are not expected to be available for servicing in the future. The most common application for splicing is joining cables in long outside plant cable runs where the length of the run requires more than one cable. There are two types of splices, fusion and mechanical. Fusion splicing is most widely used as it provides for the lowest loss and least reflectance, as well as providing the strongest and most reliable joint.
Fusion splicing machines are usually called fusion splicer available on the market that splice a single fiber or a ribbon of 12 fibers at one time. The above picture shows how to splice a fiber optic jumper. Virtually all single-mode splices are fusion. Fusion splices are made by “welding” the two fibers together usually by an electric arc. To be safe, you should not do that in an enclosed space like a manhole or an explosive atmosphere, and the equipment is too bulky for most aerial applications, so fusion splicing is usually done above ground in a truck or trailer set up for the purpose.
Today’s single-mode fusion splicers are automated and you have a hard time making a bad splice as long as you cleave the fiber properly. Fusion splicers cost thousands US dollars (up to $5,000), but the splices only cost a few dollars each. The following part display the main features of the fusion splicing:
Typical average optical losses of 0.05dB or lower
Special installation skills needed
Tools sensitive to the environment
Relatively long installation time
Standard organizer techniques required
Pre-termination is the alternative termination method popular on the market. Cables and fibers are terminated to a connector in the factory. When carefully planned, splicing jobs for specialized technicians can be limited to the network construction phase. But provisioning, churn and network testing can be performed by technicians without specific fiber skills, because the organizers can be very simple.
With pre-connectorized products, the connection time is reduced from 20 to less than 5 minutes, including the connector cleaning step. When connecting fibers with connector technology, there is no issue of environmental sensitivity. What’s more, connectors are accessible on the outside of the network element, reducing the need to access a product and the risk of disturbing other lines. The image below shows the MPO pre-terminated cables.
Factory pre-termination is also compatible with optical budget requirements by selecting the appropriate grade as defined by the international IEC standards. When properly planned, pre-connectorized
products do not add extra connectivity points, thus eliminating extra optical loss or reflections. In all, the most obvious features of the pre-terminated system lies in the following part:
Typical losses of 0.15dB or less
No special installation skills required
Reduced installation time
Very simple organizer systems
Insensitive to environmental conditions
The start-up costs for the fusion splice are significantly higher, as fusion splicers can be very expensive. Even the cheapest fusion splicer will cost nearly $2,900 (fiber-mart-F600 Fusion Splicer from fiber-mart.COM) more than the most expensive crimp kit. Not counting the initial start-up costs, splices will run anywhere from $7.20 to $8.25 per splice, which is much lower than the pre-terminated connector. The following image shows the vivid comparison between fusion splicing and pre-terminated system.