Pulling fiber optic cable requires careful technique to prevent damage to the delicate glass fibers within. Here's a breakdown of the proper method:
Preparation is Key:
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Cable Inspection: Before starting, inspect the fiber optic cable for any visible damage. Damaged cable should not be pulled.
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Conduit Inspection: Ensure the conduit or pathway is clear of obstructions, sharp edges, or debris that could damage the cable during the pull. Use a conduit brush or vacuum to clean the pathway.
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Lubrication: Apply a fiber optic cable-specific lubricant to the cable jacket and inside the conduit. This reduces friction and pulling tension. Never use petroleum-based lubricants as they can damage the cable jacket.
Pulling the Cable:
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Secure the Pulling Grip:
- Taping: Use friction tape to cover approximately three inches of the cable core and jacket. This provides a secure surface for the pulling grip.
- Positioning: Position the pulling grip (also known as a basket grip or Chinese finger trap) over the taped cable core.
- Taping in Place: Tape the pulling grip securely in place.
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Use a Swivel: Incorporate a swivel between the pulling rope and the pulling grip. This is crucial to prevent twists in the pull rope from transferring to the fiber optic cable, which can damage the fibers.
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Pulling Tension: Monitor the pulling tension at all times. Exceeding the cable's maximum pulling tension can cause significant damage. Use a dynamometer or tension meter to ensure the tension remains within specified limits. Check the cable manufacturer's specifications for the maximum pulling tension.
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Pulling Speed: Maintain a slow and steady pulling speed. Avoid sudden jerks or stops.
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Communication: If pulling over long distances or through multiple bends, establish clear communication between the pulling and feeding ends to coordinate the pull.
Important Considerations:
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Bending Radius: Never exceed the cable's minimum bending radius. Sharp bends can cause signal loss or damage the fibers. Check the cable manufacturer's specifications for the minimum bending radius.
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Qualified Personnel: Fiber optic cable pulling should be performed by trained and experienced personnel who understand the proper techniques and precautions.
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Documentation: Document the pulling process, including the pulling tension, distance, and any issues encountered.
Summary:
Successfully pulling fiber optic cable involves careful preparation, proper technique, and constant monitoring of pulling tension and bending radius. Using the right tools, including lubrication, a pulling grip, and a swivel, is essential to prevent damage and ensure a successful installation.
