How to connect the hollow cable

　　"Hollow cable" usually refers to a center tube cable (Loose Tube Cable), which is structured as follows: the center of the cable contains a plurality of loose tubes (buffer). Tubes), the optical fiber is placed in each sleeve, and there may be fillers or reinforcements between the sleeve and the jacket. This design is convenient for protecting the optical fiber, but special handling is required when connecting. The following are the connection steps and precautions:

　　Connection tools and materials

　　tool

　　optical cable stripping knife (ring cutting knife)

　　Loose tube stripper

　　Optical fiber fusion splicer

　　Optical fiber cutter

　　Cleaning tools (alcohol cotton, dust-free paper)

　　Heat shrinkable tube or fiber protection box

　　material

　　Optical cable splice box

　　Fiber patch cords (optional, for temporary connections)

　　Second, the following steps

　　1. Cable preparation

　　Peeling sheath:

　　Cut the sheath with a cable stripper (the cutting depth does not exceed the thickness of the sheath), and peel off the sheath clockwise or counterclockwise to expose the inner loose sleeve.

　　Attention: Avoid damaging the internal loose casing or reinforcement.

　　Handling loose casing:

　　Identify the loose casing to be joined (usually by color or number).

　　Cut the sleeve with a loose tube stripper, about 40-50mm in length, and gently pull out the fiber.

　　2. fiber optic processing

　　Cleaning Fiber Optics:

　　Wipe the fiber surface with alcohol cotton to remove oil stains and dust.

　　Examine whether the fiber is broken or damaged, and cut out the damaged part if necessary.

　　Cut the fiber:

　　Make a flat end face with an optical fiber cutter (the cutting angle needs to be accurate, usually 8 ° to 10 °).

　　3. Fiber optic splicing

　　Welding parameter settings:

　　Select the fusion splicer mode according to the fiber type (single-mode/multi-mode).

　　Adjust the parameters (e.g. discharge time, intensity) to achieve the best welding effect.

　　Welding operation:

　　Put the two optical fiber end faces into the V-slot of the welding machine, automatically align and weld.

　　Check the welding loss (single-mode fiber should be ≤ 0.05dB, multimode should be ≤ 0.1dB).

　　4. Protection and fixation

　　Heat shrinkage protection:

　　The heat shrinkable tube is sleeved into the fusion point of the optical fiber, and the shrinkage is uniformly heated with a heat gun to enhance the protection.

　　Or use a fiber optic protective case, filled with gel waterproof.

　　Fiber fixing:

　　The remaining length of the fiber is coiled in the splice box to avoid the bending radius being too small (single mode ≥ 30mm).

　　Close the splice box and ensure tightness.

　　III. Precautions

　　Environmental control:

　　Operate in a clean and dry environment to avoid dust contamination of the fiber optic end face.

　　Low temperature or humid environments require the use of dehumidification equipment.

　　Safe operation:

　　Wear protective glasses to prevent fiber optic debris from getting into your eyes.

　　Use professional tools to avoid pulling the fiber optic cable too hard.

　　Test Verification:

　　After the connection is completed, the entire attenuation and reflection loss are tested with OTDR (Optical Time Domain Reflectometer).

　　Compare the theoretical values to ensure that the link performance is up to standard.

　　IV. Special circumstances

　　Ribbon fiber:

　　If the fiber optic cable is a ribbon structure (multiple fibers form a ribbon unit), a ribbon fiber fusion splicer is required, and the order of the fiber optic ribbon is strictly aligned.

　　Microtubule cable:

　　For fiber-blown microtube fiber optic cable, the optical fiber needs to be blown into the microtube through the air blowing equipment, and the optical fiber needs to be processed at both ends during connection.

　　summarize

　　The connection core of hollow optical cable (center tube type) lies in the correct handling of the optical fiber in the loose tube to ensure the welding quality and environmental protection. If you have no experience, it is recommended to seek the assistance of professional engineers to avoid improper operation and cause link failure.