The termination method you choose is as important as the connector you choose. The following are the most common termination methods.
1. Connector termination options
Interface loss +’termination loss’ = true connector loss
The important note-the method you choose to terminate the fiber has a greater impact on the loss budget than the connector you choose!
The connector chart in our previous post shows the dB value of the interface loss (that is, the loss at the end of the connector). In order to accurately estimate the connector loss, you must add the additional loss generated by the termination method you choose to this value. For the convenience of discussion, we call it “termination loss”. This additional loss occurs where the connector is connected to the field fiber. Most fiber optic connectors fall into two categories; they are either “quick termination connectors” or “epoxy style” connectors.
2. Quick term vs. epoxy connector
Both quick termination connectors and epoxy connectors have their own advantages and disadvantages, depending on the application and options you choose.
- Quick-term connector options
“Quick-term” connectors provide a “quick” way to terminate optical fibers. These connectors can be polished with the end face of the clamp in the factory, so no time for on-site polishing is required. In addition, they do not require time to cure the epoxy resin.
The Quick Term Connector provides two main options:
Fast semester option 1
“Mechanical” Quick-Term Connector
Most “mechanical” quick-term connectors use mechanical equipment to fix or “splice” the field optical fiber to the fiber short section in the connector body. when…
- Speed is of the essence, such as emergency recovery
- The installer does not have the skills or experience to assemble and manually polish connectors on site
- No fusion connectors and equipment
Examples of “mechanical” quick-term connectors are:
- Corning unicam Pretium
- The short tail connector comes from Fiber Optic Instrument Sales (FIS)
- AFL quick connector
- Sumitomo Machinery Field Connector
Quick-Term option 2
“Splice-On” connector (SOC)
Similar to the “mechanical” fast term connector, the SOC fast term has a factory-polished fiber stub in the connector body. The difference is that the SOC uses a fusion splicing process to connect the fiber stub to the field fiber instead of mechanically, thereby reducing loss.
SOC generally has lower losses than field-polished epoxy connectors. The factory polishing on the SOC is more accurate than the on-site manual polishing.
Insertion loss comparison (pairing):
SOC connector:
Mating loss. 4 dB + loss per splicing<. 05 dB = 0.5 dB total loss
Field-Polished connector:
Pairing loss. 75 dB + 0 splicing loss =. 75 dB total loss
Compared with the typical hand-polished PC (-40 dB), the factory UPC polishing (-55 dB) greatly improves the consideration of back reflection.
The use of fusion splicing APC connectors provides a unique advantage-65db back reflection, ensuring high data rate performance. The field mechanical APC mating connector requires an 8 degree cutting angle, which increases insertion loss, but will reduce back reflection.
SOC also provides another “fusion splicing” terminal method, which is a significant advantage of fiber pigtails. Unlike ponytails, SOC does not require external splicing protective sleeves or splicing trays, which saves rack space.
SOC can be provided by a variety of manufacturers, including:
- Fiber optic equipment sales (Cheetah SOC)
- AFL (FuseConnect)
- Sumitomo (Lynx 2)
- Fitel and Seikoh Giken also provide SOC
Epoxy connector options
Using epoxy connectors, the field fiber will be permanently bonded to the connector ring, providing a very reliable connection. Epoxy connectors offer two options:
- Epoxy option 1
Field connector
Using this termination method, the field fiber passes through the connector body and the clamp and then polishes on-site as part of the end face of the clamp. Since splicing is not involved, there is no “termination” loss as previously defined.
advantage:
- Capable of low insertion loss and low back reflection
- Correct installation, high quality, and reliability
- Minimum cost per connector
shortcoming:
Special tools for curing epoxy resin and manual polishing
- Long assembly time (including epoxy curing time)
- Requires high-level training
- Precise end face geometry is difficult to achieve by manual polishing
Most field polished epoxy connectors use industry-standard epoxy. 3M hot melt connectors use special adhesives and do not require curing time.
- Epoxy option 2
Factory connector
Epoxy connectors can be purchased with factory polished end faces, usually as…
Pre-Ended Cable Assemblies-Custom cable assemblies are pre-ended with the connector of your choice.
Connected pigtails-factory-polished connectors with pigtails can be purchased for connection to field optical fibers.
Advantage:
Precision end surface finish can provide lower loss than manual polishing
- Training is less than manual polishing of connectors
- Quick installation
Shortcoming:
- More complex cable management
- The unit cost of pre-polished connectors is much higher than that of manual polished connectors (the material cost is higher, but the labor cost is lower)
- The connected braids have higher equipment costs (a fusion joint is required).
