Fusion Splicing and Mechanical Splicing Procedures
Fusion Splicing and Mechanical Splicing Procedures
This domain tests how a permanent fusion splice and a field mechanical splice are made, when each is used, and how the splicer's loss estimate should be treated.
Core rules and concepts
- Fusion splicing aligns the two cleaved fiber ends, usually by cladding or core alignment, and fuses them with an electric arc. Set the correct fiber type, coating diameter and splice mode. The result is a continuous glass joint with low loss and high tensile strength.
- A mechanical splice holds the fibers in a V-groove with index-matching gel. It is fast and needs no power, but loss is generally higher and gel can degrade; use it for temporary restoration or where fusion is impractical.
- Protect a fusion splice with a heat-shrink splice protector. Keep the fiber straight in the tray and respect bend radius.
- The splicer's estimated loss is a guide, not a certified measurement. Confirm with an OTDR or power-meter test.
- Re-cleave and re-splice if the estimated loss is high or the end face is bad. Do not re-arc a splice repeatedly without inspecting it.
Worked example
A 12-fiber cable must be spliced in a closure. You set the splicer to single-mode, strip and clean fiber 1, cleave at 16 mm, and place both ends in the V-grooves. The splicer estimates 0.04 dB. You place a 60 mm heat-shrink protector, heat it, and seat it in the tray. Fiber 2 shows 0.9 dB, so you open the splicer, inspect, re-cleave both ends and splice again. The second estimate is 0.06 dB. That is the correct action: investigate rather than accept a doubtful joint.
Traps that cost marks
Do not splice multimode to single-mode and expect a valid link. Do not touch the end face after cleaning. Do not skip the protector or bend the splice sharply. Do not treat the splicer estimate as the final acceptance result.