Repairing fiber optic cables in a drawer-type terminal box involves careful inspection, stripping, cleaving, splicing, and proper organization to ensure low-loss connections and reliable network performance.

Step 1: Safety and Preparation

Before starting, ensure the network is powered down to prevent eye injury from laser light. Gather essential tools: fiber optic stripper, cleaver, fusion splicer or mechanical splice kit, cleaning wipes, alcohol, and protective gloves. Open the drawer-type terminal box carefully, avoiding bending or stressing existing fibers beyond their minimum bend radius (typically 5–10 mm for bend-insensitive fibers) .

Step 2: Inspect and Identify the Fault

Visually inspect the fibers for cuts, kinks, or damaged jackets. For less visible faults, use an OTDR (Optical Time Domain Reflectometer) to locate breaks or high-loss points accurately. Mark the damaged section for removal .

Step 3: Prepare the Fiber Ends

1. Cut out the damaged section using a fiber optic cutter, leaving enough length for splicing.
2. Strip the protective jacket carefully with a fiber optic stripper to expose the bare fiber.
3. Trim aramid (Kevlar) strength members with a Kevlar cutter.
4. Clean the fiber with alcohol wipes to remove dust or oils .

Step 4: Cleaving and Splicing

• Use a high-precision fiber cleaver to create a smooth, perpendicular end-face.
• For fusion splicing, align the fibers in a fusion splicer and perform the splice to achieve a low-loss connection.
• For mechanical splicing, insert the fibers into the splice holder, ensuring proper alignment and securing the connection .

Step 5: Protect and Organize

• Place the spliced fiber into a splice tray inside the drawer box.
• Coil excess fiber neatly, maintaining the minimum bend radius to prevent signal loss.
• Cover the splice with protective sleeves or enclosures to prevent physical damage .

Step 6: Test the Connection

After splicing, use an OLTS (Optical Loss Test Set) or OTDR to measure insertion loss and verify signal integrity. Ensure the repaired fiber meets acceptable loss thresholds (typically <0.1 dB for short connections) .

Step 7: Close and Secure

Once testing confirms proper operation, close the drawer box and secure all fibers and cables. Label the repaired fibers for future maintenance and ensure the box is free from dust or debris . By following these steps, you can restore connectivity in a drawer-type fiber optic terminal box while minimizing signal loss and maintaining long-term reliability. Proper handling, precise splicing, and careful organization are key to successful fiber optic repairs.