Common Fusion Splicing Problems and How to Fix Them

Fusion splicing produces the lowest-loss joins in fiber networks, but even experienced technicians face recurring issues. Below are common problems you’ll see in the field and practical fixes to get your splices back to spec.

1. High Splice Loss

Cause: Poor cleave quality, dirty fiber endfaces, misalignment, or unsuitable fusion parameters.
Fix: Inspect the cleave under a microscope; recleave if needed. Clean fibers with lint-free wipes and isopropyl alcohol. Verify splicer settings (fiber type, mode), and replace worn electrodes.

2. Inconsistent Splice Quality (Good one day, bad the next)

Cause: Dirty electrodes, unstable power, or degraded consumables.
Fix: Clean or replace electrodes regularly. Use a stable power source — bring charged batteries or a UPS when working on unstable sites. Log electrode life and change before failures.

3. Splice Arc Failure / No Arc or Misfire

Cause: Contaminated electrodes, wrong electrode gap, or bad grounding.
Fix: Clean electrodes, check gaps per manufacturer procedure, and verify splicer firmware. Ensure splicer is on a flat surface and properly grounded.

4. Mechanical Protection Failures (Heat Shrink Shrink Issues)

Cause: Incorrect heat-protection sleeve size or improper oven settings.
Fix: Use correct sleeve diameter and follow recommended shrink oven temperatures/times. Inspect sleeves for proper shrink and adhesion after heating.

5. Fiber Breaks Near the Splice / Excessive Bend Loss

Cause: Poor fiber handling, microbends, or tight routing.
Fix: Re-route fiber with proper bend radius (typically ≥30 mm for loose-tube, check manufacturer). Use VFL to identify bends and re-work routing or add protective tubing.

Practical Troubleshooting Workflow

1. Visual inspection (cleave, contamination, fibers).
2. Clean and re-cleave if needed.
3. Check splicer settings and electrode condition.
4. Re-splice under controlled conditions.
5. Verify with OTDR and power meter. Document results.

Preventive Steps

• Keep a clean bench practice in the field.
• Track consumables and electrode hours.
• Use proper PPE and handle fibers carefully.
• Conduct periodic calibration and servicing for splicers.

Closing

Consistent, low-loss splices come from clean technique and preventive maintenance. Sangken Technologies provides on-site splicer servicing, electrode replacement, OTDR verification, and operator training to help you minimize repeat jobs.