Partner POV | A Brief Evolution of Field-Terminated Fiber Connectors

Article written and contributed by, Seamus Hamrin, Product Manager, Panduit. 

Field termination of fiber optic cable connectors is nothing new, and while there have been various products to address field termination needs over the decades, the products we will discuss here are: field polish, mechanical splice, and fusion splice. Each of these has had time in the spotlight, and there are commonalities that hold true across all three. Chief amongst these is the need for cleanliness when terminating and installing fiber, so we will not spend time on that aspect.

The three factors we shall examine are:

• Time-to-terminate
• Connector performance (Average Insertion Loss, or IL)
• Overall cost of materials and labor

Each factor has a significant impact on how easy it is to install the connectors, and the level of confidence the installer will have when they turn the job over to the end user.

Field Polish: A Vanishing Art 

Field polishing of fiber cable connectors has been around for a long time and is still used in some sectors. The average time to terminate a field polish LC connector is about 12 minutes, though shorter times are possible. While termination time is the biggest drawback, the benefits are performance and cost. The field polish method tends to have excellent IL results, and the connector cost is often lower than other options.

Mechanical Splice: The Need for Speed

Over time, the market preference shifted to mechanical splicing, most often a cam-style connector. The connector has a pre-polished ferrule with a short stub of fiber inside the connector itself, meaning the termination time could be reduced to around 2 or 3 minutes per connector. Some manufacturers chose simple, rugged metal tools that trade accuracy of the pass/fail evaluation for ease of use. Other manufacturers focused on pass/fail accuracy, at the expense of increased user difficulty. Mechanical splice connectors tend to be almost twice the price of field polish connectors, have varying levels of skill required to terminate, and have an average IL of more than 3X a field polish connector. Tool limitations, processes, and testing results have led to a noticeable decline in recent years.

Fusion Splice: The Way of the Future

Fusion splicing has also been around for decades, but the fiber splicing machines were bulky and carried a significant price tag. Over time these machines have become more compact, user-friendly, and significantly more affordable, making them accessible to even smaller firms with fewer people. Fusion splice pigtails, a length of fiber with a factory-polished connector on one end, typically have much better performance, and a lower price tag as compared to mechanical splice connectors. While pigtails offer a margin of error (because the cable can be trimmed back and the splice re-tried), the slack must be managed, and the splices must be protected in a fixture. These fixtures add to the total cost per connector and require more labor.

One of the most exciting developments is fusion splice connectors, like the OmniSplice™ connectors from Panduit. Fusion splice connectors combine all the best features:

• Terminations can be done in about 2 minutes per connector
• IL results are typically less than 0.10dB IL
• The cost of the connector is similar to the combined cost of a pigtail + additional components + added labor

Omnisplice uses a 'universal' holder that works on several common brands of splice machines and incorporates features that simplify the termination process. A high-quality fusion splice connector from a trusted manufacturer like Panduit, paired with a good fiber optic splicing machine, results in high-performance terminations, done quickly, and with less rework or scrap.