Optical fiber is the abbreviation of Optical Fiber, which is a waveguide medium that transmits light energy, and is generally composed of a core and a cladding. Junction box supplier The optical fiber transmission method has low loss and long transmission interval, which has advantages in long-distance transmission.
According to the different transmission forms of light in the optical fiber, the optical fiber can be divided into single mode fiber (SMF, Single Mode Fiber) and multimode fiber (MMF, Multi Mode Fiber).
• Single-mode fiber: The central glass core is relatively thin (10μm or less) and can only transmit one form of light. The inter-mode dispersion is small, suitable for long-distance communication.
• Multimode fiber: The central glass core is thicker (50μm, 62.5μm or larger), which can transmit various forms of light. The inter-mode dispersion is relatively large, and the transmission interval is relatively short, generally only a few kilometers.
Due to the requirement of long-distance outdoor transmission, a cable composed of multiple optical fibers encapsulated together is called an optical cable. The outer sheath of the optical cable is generally black with steel wire protection inside. According to different types of optical fiber encapsulated by junction box manufacturers, optical cables are divided into single-mode and multi-mode.
Fibers with connectors at both ends are jumper fibers. Patch cords are used to make jumpers from equipment to optical fiber wiring links, and are generally used to connect optical transceivers and terminal boxes. Common fiber jumpers include single-mode fiber jumpers and multi-mode fiber jumpers.
• Single-mode fiber jumper: The outer skin is generally yellow, the connector and protective cover are blue, and the transmission interval is longer.
• Multi-mode jumper fiber: The outer skin is generally orange, the connector and protective cover are beige or black, and the transmission interval is short.
According to the interface type, fiber jumpers are also divided into SC fiber jumpers, LC fiber jumpers, FC fiber jumpers and other types. The length of the patch cord is generally 0.5m, 1m, 2m, 3m, 5m, 10m, etc.
Junction box specifications
As long as there is a connector at one end and the fiber with a broken core at the other end is a pigtail. The pigtail is connected to the core of the optical cable through fusion splicing, and often appears in the optical fiber terminal box, and is mainly used to connect the optical cable and the optical fiber transceiver. (Fiber splicing refers to the use of a fiber fusion machine to connect the optical fiber and the optical fiber or the optical fiber and the pigtail, fusing the bare fiber and the optical fiber pigtail in the optical cable into a whole.)
Pigtails can be divided into single-mode pigtails (yellow) and multi-mode pigtails (orange). According to the interface type, the pigtails are also divided into SC pigtails, LC pigtails, FC pigtails and other types.
Fiber optic connector
The optical fiber connector is an indispensable passive component in the optical fiber communication system. The specification of the junction box completes the detachable connection between the optical channels, making the commissioning and maintenance of the optical system more convenient. There are many types of fiber optic connectors.
Precautions for use
When using optical fiber for connection, please pay attention to the following:
• Please confirm whether the type of optical fiber connector and optical fiber conform to the type of pluggable interface module selected.
• The optical interfaces on some supporting boards of the SR8800-X router have shielding plugs. When these optical interfaces need to be used, the shielding plugs must be removed first. Please keep the removed shielding plugs properly. When these optical interfaces are no longer used, you need to reinstall the shielding plugs on these optical interfaces.
• There is a dust cap on the optical fiber connector. When using the optical fiber connector, please keep the dust cap properly. When it is no longer in use, the fiber connector must be covered with a dust cap to avoid scratching the end face of the fiber connector ferrule during the assembly process and affecting its performance indicators. If the dust cap is too loose or contaminated, please replace it in time.
• Before using the optical fiber connection, please wipe the end face of the optical fiber connector ferrule with lint-free paper dampened with absolute alcohol. When scrubbing, you can only wipe in one direction. At the same time, wipe the end face of the optical fiber connector that is connected to it.
• Do not twist or bend the optical fiber. The bending radius of the optical fiber after the installation shall not be less than 40mm (the minimum bending radius is 20D under dynamic bending, 10D under static conditions, and D is the outer diameter of the optical fiber dust cap).
• When connecting, if the optical fiber needs to pass through the metal plate hole, then the metal plate hole should have a smooth and fully rounded appearance (rounding radius R should not be less than 2mm), passing through the metal plate hole and along the structure When turning sideways, a protective cover or pad should be added.
• Do not use excessive force when plugging or unplugging the optical fiber connector to prevent pulling, pressing, or squeezing the optical fiber.