When installing a fiber optic cable, choosing the most appropriate fiber connector type is crucial. This blog post will provide an overview of the most common fiber connector types, highlighting their pros and cons to help you make an informed decision. A fiber connector, also known as a termination, allows you to easily connect and disconnect fiber cables. Many fiber connector types feature a spring-loaded connection that maintains a constant force between the two fibers, ensuring a strong and reliable connection.
Typically, there are three main components to the construction of a connector: the Boot, the Body, and the Ferrule.
Ferrules are most commonly made of a material called zirconia. In the early days of connector manufacturing, the ferrules were constructed of stainless steel. Zirconia offers lots of advantages over other materials such as being free from cracks, chips, or imperfections; a smoother finish due to smaller grain; a thermal expansion coefficient very close to that of fiber; very high-impact resistance; and a high modulus of elasticity.
ST Fiber Connector Types
These connectors use a 2.5mm ferrule that is mounted on the inside of the housing. This is an older style connector but is still commonly used in multimode applications.
Advantages: The ST connector, while older, is still commonly in use in today’s fiber installations due to it being extremely easy to install and its relatively low cost compared to some other connectors. This connector has a keyed “slot” on the end of the connector that helps keep it tightly mated to the fibers and in alignment when they are decoupled and recoupled.
Disadvantages: ST Connectors have a round shape to them and are not as compact as more modern square-body connections. Also, with this being a spring-loaded connection, the installers must push the connector with quite a bit of force and turn the nut to use these connectors.
SC Fiber Connector Types
The SC connector was invented to directly replace the ST connectors and, as a result, has become one of the most common fiber connectors in the world. Similar to the ST connector, this SC style also utilizes a 2.5mm ferrule.
Advantages: The SC connector is what is called a non-optical disconnect connector. This means that once the connector has been installed, any pushing or pulling on the jacket of the cable will not cause the ferrule to disconnect. The square shape of these connectors offers a more compact design which means more of these connectors can be installed in a smaller footprint of space. SC connectors are ideally suited for datacoms and telecoms.
Disadvantages: The main disadvantage of an SC connector is that although its square body is easier to insert/take out, the body is larger than the LC connector which means it will take up more room than its newer cousin.
FC Fiber Connector Types
The FC connector also utilizes a 2.5mm ferrule. This connector shares a round profile like the ST connectors but instead of a spring-loaded twist lock mechanism, this connector has a threaded connection.
Advantages: Like the SC connector, the FC connector also has a non-optical disconnect advantage. Because this connector threads onto a connection, you can be sure that this connector will stay stable and mated to its connection, even during rougher environments.
Disadvantages: Very similar to the ST, this connector can be hard to grab and twist to thread or unthread from a connection if there are lots of connectors in one receptacle.
LC Fiber Connector Types
LC Connectors were invented by Lucent Technologies (hence the LC name). This is a member of what is referred to as the small form factor (SFF) line of connectors. The LC connector uses a 1.2mm ferrule and has about half the footprint size of the other connectors.
Advantages: You can quickly convert these instruments from a simplex connector to a duplex connector with the use of a clip. They are low-loss connectors and are also pull-proof. The SFF design makes this the perfect connection for a high-density application, which is why this is the connection of choice for networking and transceivers.
Disadvantages: The SFF design makes it hard to grasp as it is so tiny and often in a densely populated application. There are LC extraction tools that can help with this.
MTP/MPO Fiber Connector Types
These connectors are used for ribbon cables. In single-mode use, these will typically get about .25dB loss and about .20dB loss in multi-mode. MTP connectors are usually considered a high-performance option while MPO are better for mechanical uses.
Advantages: MPO/MTP connectors combine 8, 12, or 24 fibers into one single and compact interface. They can put this amount of cable in the same space an SC connector would take up, effectively saving rack space on a high-density rack.
Disadvantages: An MPO/MTP connector is not the easiest to clean because there are so many fibers in one connection.