What is  fiber optic pigtail?

Fiber optic pigtail is a short, typically tight-buffered, fiber optic cable with a factory-installed connector on one end and unterminated fibers on the other. The connector side can be connected to equipment, while the other end is either fusion-spliced (in the case of fusion splicing) or mechanically spliced (in the case of mechanical splicing). Fiber optic pigtails are used to connect fiber optic cables together, either by fusion splicing or mechanically splicing. High-quality pigtails, combined with appropriate splicing techniques, provide optimal performance for fiber optic cable termination. Fiber optic pigtails are commonly found in fiber management equipment such as optical fiber distribution frames (ODFs), fiber optic terminal closures, and patch panels.

What is the difference between a fiber optic pigtail and a fiber optic patch cord?

A fiber optic pigtail has only one end plugged into a fiber optic connector; the other end is unconnected. A fiber optic patch cord has fiber optic connectors attached to both ends. Patch cord fibers are typically jacketed; however, fiber optic pigtails are typically unjacketed because they are spliced and protected in a fiber optic splice closure. Furthermore, patch cord fibers can be split into two sections, creating two pigtails. Some installers prefer to avoid the hassle of testing the pigtails in the field—they simply test the performance of the fiber patch cord and then cut it in two to create two fiber pigtails.

Types of Fiber Pigtails: Fiber pigtails are categorized by fiber type as either multimode or single-mode. Multimode pigtails are made from 62.5/125μm or 50/125μm bulk multimode fiber and terminated with a multimode connector. More specifically, they can be categorized as OM1, OM2, OM3, OM4, and OM5 pigtails. Single-mode pigtails are made from 9/125μm OS1 or OS2 bulk single-mode fiber cable and terminated with a single-mode connector.

Classification by Connector Type: Fiber pigtail connectors come in a variety of types, such as LC pigtails, SC pigtails, ST pigtails, FC pigtails, MT-RJ pigtails, E2000 pigtails, and more. Fiber pigtails can be classified into three types: FC, SC, and LC. The two ends are: FC-FC, SC-SC, LC-LC, FC-SC, FC-LC, and SC-LC, for a total of six fiber optic patch cord types.

Based on the interface polish type, they can be classified into PC, UPC, and APC fiber pigtails.

PC fiber pigtails: PC stands for “physical contact” connector. PC fiber pigtails are made with a connector that has a physical contact polish. Most multimode fiber pigtails use PC-polished connectors and are widely used in telecommunications and data systems.
UPC fiber pigtails: UPC stands for “ultra-physical contact.” Unlike PC fiber pigtails, these pigtails are made with UPC connectors, which improve physical contact performance, thereby reducing air gaps and further reducing optical loss (ORL). It is the most common polish type for single-mode and multimode fiber pigtails.
APC fiber pigtails: APC stands for “angled physical contact.” It is designed to further reduce back reflections. The ferrule endface of these connectors is polished at an 8-degree angle. APC fiber pigtails are commonly used in CATV, FTTx, and other WDM systems.

Benefits of using fiber pigtails include:

Simplified installation: Prefabricated pigtails allow for quick connection, saving installation time.

Reduced signal loss: Precision factory connections reduce insertion loss and reflections.

Increased reliability: Rigorous quality control reduces failure rates.

Easy maintenance: Easy replacement and troubleshooting.

Enhanced cleanliness: Simplified fiber routing reduces clutter.

Fiber pigtails improve the efficiency, stability, and manageability of fiber networks.