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OTDR MAINTENANCE TOOL

OTDR Event Analyzer

Enter or import multiple OTDR events, compare two wavelengths, identify event types and generate maintenance priorities. Version 1.0 focuses on event-table diagnosis and does not parse SOR files directly.

Multi-eventDual wavelengthDead-zone checkCSV import
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Test settings and thresholds

All thresholds are editable engineering defaults.

These thresholds are editable engineering defaults, not universal pass/fail criteria for every operator, vendor or acceptance scenario.
OTDR test settings
km
dB/km
dB/km
Event classification thresholds
dB
dB
dB
dB
dB
dB
dB
m
m
m
m
OT

Event analysis result

Summary, topology, event classification and maintenance actions.

Overall status—
Events0
Abnormal0
Critical0
Maximum event loss0 dB
Estimated primary loss0 dB
Estimated secondary loss0 dB
Reflective events0
Dead-zone affected0

Event position topology

OTDR event input table

Swipe the tables horizontally on mobile to view every column.

No.Distance (km)Primary loss (dB)Secondary loss (dB)Reflectance (dB)Cumulative (dB)Manual typeNote / action

Event diagnosis table

Swipe the tables horizontally on mobile to view every column.

No.DistancePrimary lossSecondary lossReflectanceDetected typeSeverityGap (m)ReasonRecommended action

Priority diagnosis and actions

METHODOLOGY

Methodology

Non-reflective events

Low-loss events are normally treated as splices. Higher loss increases severity according to editable thresholds.

Reflective events

Reflectance above the configured threshold indicates a connector, mechanical joint or strong reflective fault.

Bend comparison

A larger loss at the secondary wavelength can indicate macro- or micro-bending when the event is non-reflective.

Dead-zone check

Spacing from the previous event is compared with event and attenuation dead-zone defaults.

Event classification is a rule-based engineering aid. Always review the original OTDR trace and test context.

FAQ

Frequently asked questions

Are OTDR event thresholds universal?

No. Thresholds vary by operator, vendor, link type, wavelength, pulse width and acceptance rules. This tool keeps them editable.

Why compare 1310 nm and 1550 nm?

Bending loss often increases more at longer wavelengths. A wavelength difference can support bend diagnosis, but it is not a standalone conclusion.

What is a ghost event?

A ghost can appear at a multiple of the distance to a strong reflector and may show little real insertion loss. Change pulse width and range to verify it.

Can this tool parse SOR files?

Version 1.0 analyzes event-table data and CSV imports. Direct SOR parsing is reserved for a later version.

Why can nearby events be unreliable?

Events inside the event or attenuation dead zone can overlap, making reflectance or loss difficult to separate.

Should results replace field judgment?

No. Use the original trace, bidirectional tests, route records, power measurements and field inspection.

REFERENCES

Standards and engineering references

Last reviewed: 2026-09-01. These sources support optical-fibre measurement methods, terminology and component characteristics. Editable thresholds remain planning defaults and must be checked against the OTDR settings, cable specification and acceptance contract.

PROJECT RECORDS

History

ENGINEERING WORKFLOW

Continue the engineering workflow

Current workflowOptical Fault Isolation Workflow

Start from measured ONU receive power, locate abnormal events, then compare field loss with the design budget.

Step 2 of 4
PreviousONU RX Power DiagnosisDiagnose normal, weak-light, overload or possible no-signal conditions from measured power.NextFiber Loss CalculatorCalculate fiber, splice, connector, splitter and engineering losses for an optical link.

Related tools

Fiber Loss CalculatorCalculate fiber, splice, connector, splitter and engineering losses for an optical link.ONU RX Power DiagnosisDiagnose normal, weak-light, overload or possible no-signal conditions from measured power.Optical Power Budget CalculatorVerify an optical link using transmit power, receiver sensitivity, optical penalty and ODN loss.