Search FAHMY
Theme

Sunlight is maximum contrast for direct sun.

SPL Splicing SPL-11 Step 11 of 13

Testing and Acceptance

Prove every fiber meets the owner's acceptance criteria with bidirectional OTDR and power meter tests, and keep the files.

ChecklistOn the Map

Crew

  • Test Technician
  • Lead Splicer
  • Owner or Inspector

Hazards

  • Invisible Laser Light from Test Sources and Live Fibers
  • Glass Fiber Shards

Purpose

Prove that every fiber meets the owner’s acceptance criteria, and keep the files to show it. The test results are what the owner pays on and what the next technician uses to find a fault. A splice is not done until it is tested and accepted.

When to Do It

  • After splicing is complete (SPL-07, SPL-08) and trays are organized (SPL-09).
  • Verification shot: with each closure still open, before it is sealed (SPL-10), where the owner’s process allows.
  • Final acceptance: after every closure on the link is sealed, mounted and its slack stored, per the owner’s process. End-to-end bidirectional OTDR and power meter tests need the whole link spliced.
  • Previous step: SPL-10 Closure Sealing, Grounding and Mounting. SPL-10 and SPL-11 run together; see the order below. Next step: SPL-12 Documentation and Handoff.

Roles

  • Test technician: sets up the OTDR and power meter, shoots and saves traces, and names files.
  • Lead splicer: re-splices failed events and coordinates closure access.
  • Owner or inspector: sets the acceptance criteria and reviews results.

Equipment and Materials

Safety

Procedure

  1. Run a verification shot while each closure is open, where the owner’s process allows.
    • Shoot per the owner’s process, for example an OTDR shot from an accessible point, to catch bad splices before the closure is sealed.
    • Re-splice any failed event now, while the closure is open.
    • This shot is not acceptance. Steps 2 to 11 are the acceptance test.
  2. Confirm the link is finished before acceptance testing.
    • Every closure on the link is sealed, mounted and its slack stored (SPL-10), per the owner’s process, so closing and coiling cannot add bends after you test.
  3. Inspect and clean every connector before mating.
    • Inspect with a scope, clean, and inspect again until the end face meets the owner’s criteria. IEC 61300-3-35 defines connector end-face inspection criteria.
    • Clean the test cable connectors too, so a dirty test lead does not fail good fiber.
  4. Set up the OTDR.
    • Use launch and receive cables so the first and last connectors are measured.
    • Test at the owner’s wavelengths: per owner spec.
    • Use the pulse width, range and averaging the owner specifies: per owner spec.
  5. Shoot traces from both ends, per the owner’s test method (bidirectional testing is common practice).
    • Test every fiber from end A to end B, then from end B to end A.
  6. Report each splice’s loss as the average of the two directions, per the owner’s test method.
    • Average = (A→B + B→A) ÷ 2.
    • One-direction readings can show gainers: an apparent negative loss from a backscatter mismatch between the two fibers. The average gives the true loss.
    • Use the OTDR Splice Average tool to compute averages and flag events over the owner’s threshold.
  7. Look for macrobends.
    • An event with noticeably higher loss at 1550 nm than at 1310 nm usually means a macrobend: a tight bend in a tray or a slack coil.
    • Find the event distance on the trace and check that tray or coil. See Reading OTDR Traces for how a macrobend and other events look on a trace.
  8. Measure end-to-end loss with a light source and power meter.
  9. For a passive optical network (PON), measure power at the terminal or ONT location.
    • Use a PON power meter and confirm the reading is within the ONT’s receive range: per ONT manufacturer and owner spec.
  10. Re-splice and re-test failed events.
    • Compare with the open-closure verification shots. A new event that was not there with the closure open is usually a bend added during closing or coiling.
    • Re-splice or re-route any event over the owner’s threshold (per owner spec), re-enter the closure per the owner’s process, and re-test it from both ends.
  11. Save every acceptance file named by fiber id.
    • Save the bidirectional OTDR traces and the power meter results from steps 5 to 10 as the acceptance files.
    • Use the owner’s naming convention, so each trace can be matched to its fiber years from now.

Hold Points

Records to Keep

  • Acceptance files: OTDR trace files from both directions for every fiber, taken on the finished link, named by fiber id.
  • Bidirectional average loss per splice.
  • Light source and power meter results per fiber, with the reference method used.
  • PON power readings at terminal or ONT locations.
  • List of re-spliced events and their re-test results.
  • Open-closure verification shots, where taken, per the owner’s process. These are not the acceptance files.

Common Mistakes

  • No launch cable. The OTDR cannot measure the first connector, and the last connector hides at the end of the trace.
  • One-direction acceptance. Gainers and inflated losses lead to wrong pass or fail calls. Test both directions and average, per the owner’s test method.
  • Dirty connectors. Many “bad fiber” calls are dirty end faces. Inspect and clean every time.
  • Calling the open-closure shot acceptance. It shows the splices before closing, mounting and coiling, which can add bends. Acceptance is the bidirectional test on the finished link.
  • Testing before closures are finished, then disturbing them. Every closure on the link must be sealed, mounted and its slack stored before acceptance testing, per the owner’s process.

Standards and References

  • IEC 61300-3-35 for connector end-face inspection criteria.
  • ANSI/TIA-568.3 for splice loss limits and loss measurement reference methods.
  • ANSI Z136.2 for safe use of optical fiber communication systems.
  • OTDR and power meter manufacturer instructions.
  • Owner acceptance criteria: wavelengths, splice loss, reflectance and naming.
  • Reading OTDR Traces for how splices, connectors, gainers, bends, ghosts and breaks look on a trace.

On the Map

  • OTDR Splice Average: bidirectional average splice loss with gainer flags and pass or fail against the owner’s threshold.
  • Optical Loss Budget: the expected end-to-end loss to compare with power meter results.

SPL-11 · Field Checklist

Checklist

0/14items ticked

Tick each procedure step and hold point as the crew completes it. Ticks stay on this device only. They are a personal aid, not a hold-point release or a project record; follow the owner’s sign-off process.

Procedure
Hold Points

OSP Map · Plan View

On the Map

Open the map
  • OTDR with Launch CableInstrument that maps loss and reflectance along a fiber; launch and receive cables reveal end connectors.Drawn in the handhole detail
  • Fiber Distribution HubCabinet with splitters that links feeder fibers to distribution fibers.
  • Splitter ModulePassive optical splitter that divides one feeder fiber among several distribution fibers.

Tools and Terms

Related Tools

  • OTDR Splice AverageAverage bidirectional OTDR readings for splice loss, with pass or fail against the owner's threshold.
  • Optical Loss BudgetAdd up optical link loss, compare it with the optics, and show headroom and loss-limited reach.

Glossary Terms on This Page

Report an Issue

Spotted something wrong or out of date? Emailfeedback@fahmy.iowith the step and version (SPL-11, v1.0.0) and what you saw in the field.

FAHMY is a reference, not a substitute for owner specifications, the authority having jurisdiction, manufacturer instructions, training or qualified supervision. Follow your employer's safety program and all applicable laws.

Operations

More

Theme

Sunlight is maximum contrast for direct sun. Auto follows your device.