Comprehensive Analysis Of The Differences Between Fiber Optic Patch Cord And Pigtail And Precautions For Use

Fiber pigtails and fiber patch cords are two commonly used network connection devices in fiber optic networks. They have many similarities, so many people cannot tell the difference between the two and often confuse them. In fact, the most intuitive difference between the two is that the pigtail has a connector only at one end, while the patch cord has connectors at both ends.

Fiber optic patch cord: Also called fiber optic connector, it has connectors at both ends. It is similar to coaxial cable, but without mesh shielding layer. It is used as a patch cord from equipment to fiber optic wiring link. It is generally used for connection between optical terminal and terminal box.

Several commonly used fiber optic patch cords in network engineering are:

1. FC fiber optic patch cord: The external reinforcement method is a metal sleeve, and the fastening method is a screw buckle. It is generally used on the ODF side. (Most used on patch panels)

2. SC fiber optic patch cord: A connector for connecting GBIC optical modules. Its shell is rectangular and the fastening method is a plug-in latch type, which does not require rotation. (Most used on router switches)

3. ST fiber optic patch cord: Commonly used in fiber optic patch panels, the shell is round and the fastening method is a screw buckle. (For 10Base-F connections, the connector is usually ST type. Commonly used in fiber optic patch panels)

4. LC fiber optic patch cord: A connector for connecting SFP modules. It is made of a modular jack (RJ) latch mechanism that is easy to operate. (Commonly used in routers)

Fiber pigtail: Also called pigtail, one end is the connector and the other end is the broken end of the fiber core of the optical cable. It is mainly used to connect the optical cable to the optical transceiver (couplers, jumpers, etc. are also used in between). It usually appears in the optical fiber terminal box and is connected to other optical cable cores by fusion splicing, which can simplify the installation and maintenance of the cable system.

Types of fiber pigtails

Pigtails are generally divided into single-mode pigtails and multi-mode pigtails. The wavelengths of single-mode pigtails are 1310nm and 1550nm, and the transmission distances are 10km and 40km respectively; the wavelength of multi-mode pigtails is 850nm, and the transmission distance is 500m, which is used for short-distance interconnection. FS pigtails are all made of precision ceramic ferrules, which have strong anti-pressure and drag performance and meet Telcordia, EIA/TIA standards.

The commonly used pigtails in the transmission system have five types of interfaces: LC, SC, ST, FC, and LSH. The shape and color of the connectors are the same as those of the corresponding types of jumpers.

In addition to the above categories of pigtails, there are also bundled pigtails and ribbon pigtails. Both types of pigtails are branchable pigtails and are rarely used for civilian use. Bundle pigtails are mostly used in industrial projects, and ribbon pigtails are mostly used in large-scale communication projects such as telecommunications and mobile.

Connection method of optical fiber pigtails

Optical fiber pigtails provide interconnection and cross-interconnection applications in the network connection of access equipment. They are widely used in optical fiber CATV networks, FTTH/FTTX, telecommunications networks, pre-terminated installations, optical fiber data transmission, LAN/WAN networks, etc. They often appear in optical fiber distribution frames, optical fiber terminal boxes, and optical fiber distribution frames, and are connected to other optical cable cores to produce effects.

There are two ways to connect optical fiber pigtails: mechanical splicing and fusion splicing:

1. Mechanical splicing

After peeling off the outer skin of the laid optical fiber and pigtail, cutting and cleaning them, they can be inserted into the splicing matching plate for alignment, tangency and locking.

2. Fusion

After the fusion splicing tool is ready, use wire strippers to peel off the outer skin of the laid optical fiber and fiber, clean the bare fiber with alcohol cotton, cut the optical fiber with a fiber cutter, and then use the fusion splicing tool to fuse them together under the protection of the fusion splicing tray.

Precautions for jumpers and pigtails

① The optical modules connected by the jumpers must have the same transmit and receive wavelengths. Generally, short-wave optical modules are paired with multi-mode jumpers, and long-wave optical modules are paired with single-mode jumpers to ensure the accuracy of data transmission.

② The jumpers should be wired in such a way that the number of turns is reduced as much as possible, which can reduce the attenuation of optical signals during transmission.

③ The connectors of the jumpers should be kept clean. After use, the connectors should be encapsulated with protective covers to prevent oil stains and dust from entering. If stains are found, use a cotton swab dipped in alcohol to clean them.

④ The pigtail is relatively thin, and the cross-section of the pigtail is at an angle of 8 degrees. It is not resistant to high temperatures and will break if it exceeds 100°C. Therefore, it should be avoided in high temperature environments.