Variations in Fiber Optic Connectors Last Updated: 01/31/2017
Male plugs used in the termination of fiber optic cable and designed with a ferrule that will secure the fiber strand within the plug’s housing and ensure it will mate properly with its intended fiber optic port or coupler.
Ferrules are composed of either zirconia ceramic, polymer composite or steel.
There are over 100 varieties of fiber optic connectors on the market. The types discussed in this article represent, by far, the most common types in use.
Connection of components within a fiber optic network for high speed data transfer with less signal loss, greater bandwidth and distance than copper, and no susceptibility to many of the problems that plague copper cable (i.e. EMI/RFI, crosstalk).
In general, three principles should be followed to match ferrule materials with a given application:
In mission critical, permanent link and patch cord applications, it is recommended that zirconia ceramic ferrule products be deployed.
In any dynamic application (such as a patch field) the durability of ceramic solutions is preferred.
In more static interconnect environments (such as behind walls, at consolidation points, or in telecommunications rooms) composite solutions are a cost-effective and standards compliant choice.
The 2.5mm ferrule used in SC, ST and FC connectors allow them to be inter-connected.
ST style fiber connectors have declined in popularity in recent years; however, some installers prefer them in industrial or machine applications where equipment vibration may be an issue. The twist-lock design tends to be less susceptible to unintentional disconnect compared to some other types of connectors.
APC – Angled Physical Contact connectors (a.k.a. angle polish connectors) are primarily used with single-mode fiber networks where back reflection may be an issue. The angle, which is 8 degrees, minimizes light being reflected back thus improving performance. Some single-mode network equipment use other methods to minimize back reflection, so not all single-mode networks need this type of interface.
MT-RJ - fiber optic connector designed to house two fiber strands within a single ferrule.
UPC - ferrule endface of an Ultra Physical Contact connector is ultra-polished (by hand or machine) to create a convex shape to tightly match the connecting ferrule endface.
Cam termination - style of fiber optic connector that employs a cam lock and clamping mechanism to retain the fiber and buffer within the connector housing. Fiber stubs are factory installed inside the ferrule which eliminates the need for polishing in the field and epoxy adhesives. The cam termination creates a mechanical splice, and its simple and fast design makes it suitable for field termination.
MAC – moves, adds, changes associated with network installs
MPO - multi-position optical (a.k.a. multi-fiber push-on) fiber optic connector used for high density applications. The MPO connectors may terminate 12, 24, 36, 48, 60 or 72 fiber strands in a single housing. There are male and female versions of the MPO more commonly referred to as “pin” and “no pin” variations. These pins and holes serve to align the fiber strands when mated. The MPO will also be keyed for either up or down installation as related to the numbering sequence of the fibers to be aligned.
MTP - a trade mark protected MPO connector manufactured by US Conec.
Pre-polished - used in reference to field-installable fiber optic connectors with ferrule endfaces pre-polished by the manufacturer, thereby ensuring a precision shape and eliminating the need to polish at the job site.
Meter - fiber optic distances are typically expressed in meters. 1 meter is equal to 3.28 feet (39.37 inches).
Wavelength - the distance from one energy wave to another. Fiber optic cable uses longer wavelengths in the infrared to minimize attenuation.
Bandwidth - refers to the range of signal frequencies within which a fiber optic channel will operate.
Nanometer - equal to 1 billionth of 1 meter. It is used in fiber optics to express the wavelength of transmitted light.
Attenuation - loss of signal over the length of a network link.
Insertion Loss - signal loss due to the insertion of an additional component or the creation of a splice within a continuous path.
* Nippon Telephone & Telegraph
Common Ferrule Materials:
Good tolerance to mechanical shock, humidity, temperature
Conforms to TIA/EIA-568-B.3 and IEC/ISO 11801
Can result in more surface markings from filler particulates left behind during polishing
Not recommended for patch cables
Material degrades over multiple matings during MACs
Best option for repeated matings during MACs
Precision core-to-core alignment
Greater control of grain size allows finer polishing & repeatable geometry
Excellent tolerance to mechanical shock, humidity, temperature