The dedicated failure-classification section for AGL testing, verification, commissioning and acceptance activities — connecting the Failure Database directly with the AGL Testing & Commissioning Manual. Covers electrical testing, functional and photometric performance, cable and connector testing, control and system integration, FAT/SAT, test-equipment calibration and commissioning control across 20 failure categories.
Key principle — A system can appear operational during a normal visual inspection while still failing an electrical, photometric, alignment, functional, integration or acceptance test. Division 17 creates a structured path from Test → Test Result → Failure → Investigation → Corrective Action → Retest → Acceptance.
Diagnostic principle — Not every failed test is an equipment failure. Some findings originate from test equipment, calibration, test procedure, measurement error, configuration or the commissioning process rather than the AGL asset itself — always establish which side of that line a finding sits on before it is logged as a technical failure.
An insulation-resistance test does not achieve the applicable acceptance criterion.
Required electrical continuity cannot be demonstrated during testing.
A continuity-test failure is a test finding. The underlying failure should subsequently be classified under the appropriate technical division, such as cable, connector or wiring failure.
Measured earth resistance does not meet the applicable acceptance criterion.
Cross-reference Division 15 — Earthing & Bonding Failures.
An isolation transformer or associated transformer does not pass the applicable testing requirements.
Cross-reference Division 04 — Isolation Transformer Failures.
A Constant Current Regulator does not meet the applicable testing requirements.
Cross-reference Division 03 — CCR Failures.
AGL equipment or system does not perform its intended function during functional testing.
Determine whether the failure originates from:
Lighting equipment or system does not satisfy the applicable photometric-performance requirements during testing.
A fixture can pass a functional ON/OFF test but fail a photometric test. Therefore these must remain separate failure categories.
PAPI/APAPI installation does not satisfy the required alignment/elevation/orientation criteria during testing.
Cross-reference Division 11 — PAPI/APAPI Failures.
An airfield sign does not satisfy the applicable acceptance-test requirements.
Cross-reference Division 12 — Airfield Sign Failures.
A cable does not pass the applicable electrical or installation test.
Cross-reference Division 02 and Division 05.
A connector or connector assembly does not pass the applicable testing/verification requirement.
Cross-reference Division 05 — Cable & Connector Failures.
The ALCMS does not successfully integrate with the AGL equipment/control system during testing.
Cross-reference Division 07 — Control System Failures.
Equipment or system does not satisfy the applicable requirements during Factory Acceptance Testing.
Equipment or system does not satisfy the applicable requirements during Site Acceptance Testing.
FAT failure primarily identifies a failure during factory verification. SAT failure identifies a failure during site acceptance. They should not be merged into one category.
Two or more AGL subsystems do not operate correctly together during integration testing.
Identify whether the failure originates at:
The completed system does not meet the required performance criteria during acceptance.
A system can pass individual component tests but fail system-level performance acceptance. This is why the category remains separate:
Test equipment or measurement instrumentation is found to have invalid, expired or otherwise unacceptable calibration status for the intended test.
Cross-reference Division 25 — Test Equipment, Calibration & Engineering Quality.
A test result is determined to be incorrect, invalid or inconsistent with the actual condition of the equipment/system.
An incorrect test result is not automatically an equipment failure. The investigation must establish whether the problem was equipment failure, or testing/measurement failure.
Equipment/system remains non-compliant or unsuccessful after corrective action and subsequent retesting.
A failed retest should trigger deeper RCA, rather than repeated corrective actions without identifying the underlying cause.
A deviation from the approved commissioning requirement, procedure, design, specification, sequence or acceptance condition.
A commissioning deviation does not necessarily mean the equipment itself has failed. It means the commissioning condition or process has deviated from the approved requirement.
Diagnostic matrix, failure chains, the test-failure-vs-equipment-failure principle, structured failure record and severity linkage that apply across all 20 Division 17 Testing & Commissioning failure topics.
Quick-reference mapping of each failure to its primary investigation focus:
| Failure | Primary Investigation |
|---|---|
| Insulation-resistance test failure | Insulation/cable condition |
| Continuity-test failure | Electrical continuity |
| Earth-resistance test failure | Earth system |
| Transformer-test failure | Transformer condition |
| CCR-test failure | CCR performance |
| Functional-test failure | Functional operation |
| Photometric-test failure | Optical/photometric performance |
| PAPI alignment failure | PAPI geometry/alignment |
| Sign acceptance-test failure | Sign performance |
| Cable-test failure | Cable condition |
| Connector-test failure | Connector condition |
| ALCMS integration-test failure | Control/integration |
| FAT failure | Factory acceptance |
| SAT failure | Site acceptance |
| System integration failure | Subsystem interfaces |
| Performance acceptance failure | Overall system performance |
| Calibration failure | Test-equipment validity |
| Incorrect test result | Measurement/data validity |
| Failed retest | Corrective-action effectiveness |
| Commissioning deviation | Compliance with commissioning requirements |
Record the full test-to-acceptance chain, not just the final pass/fail result.
This distinction is built into the Failure Database — every Division 17 record should separate the testing failure from the technical failure it reveals (or fails to reveal):
Cable insulation breakdown → Insulation-resistance test failure. The technical failure is the cable insulation breakdown; the testing failure is the insulation-resistance test failure.
Incorrect test setup → Incorrect test result. Here the equipment may actually be healthy — the failure is associated with the testing process, not necessarily the AGL equipment.
PAPI physically misaligned → PAPI alignment failure → PAPI alignment test failure. Division 11 records the physical/technical PAPI failure; Division 17 records the testing/commissioning failure. This cross-linking is important.
Every failure receives a severity classification, plus operational-impact tagging:
Critical / Safety-Critical — immediate operational or safety risk
Major / Operationally Critical — significant availability impact
Moderate — reduced performance, not yet critical
Minor / Non-Critical — limited or no operational effect
Degradation / Intermittent / Latent — developing or hidden fault
Every Division 17 failure should have a structured record containing at minimum:
Test Identification
Test Equipment
Test Requirement
Failure
Investigation
Corrective Action
Retest
Acceptance
Reliability
Division 17 is the quality-control bridge between the AGL equipment failure database and the AGL Testing & Commissioning Manual. A failed test is a finding, not automatically a verdict — always establish whether the root cause sits with the asset (cross-reference the relevant technical division — CCR, cable/connector, earthing, PAPI, signs, transformer, control system), the test process (procedure, setup, interpretation), or the test equipment (calibration, instrument condition). This prevents an important reliability-reporting error: counting every failed test as an equipment failure when some failures actually originate from test equipment, calibration, test procedure, measurement error, configuration or the commissioning process.
Quick answers about testing and commissioning failures, as covered in Division 17 of the AGL Failure Database.
Division 17 covers failures in testing and commissioning, and links the Failure Database directly with the AGL Testing & Commissioning Manual. It contains 20 published topics (TCF-01 to TCF-20) covering electrical testing, functional and photometric performance, cable and connector testing, control and system integration, FAT/SAT, test-equipment calibration and commissioning deviations.
Insulation-resistance, continuity, earth-resistance, transformer and CCR test failures, functional-test and photometric-test failures, PAPI alignment failure, sign acceptance-test failure, cable-test and connector-test failures, ALCMS integration-test failure, FAT and SAT failures, system integration failure, performance acceptance failure, calibration failure, incorrect test result, failed retest and commissioning deviation.
They fall into six groups: Electrical Testing Failures (5 topics), Functional & Performance Testing (4), Cable & Connector Testing (2), Control & Integration Testing (5), Test Equipment & Data Quality (2) and Retest & Commissioning Control (2).
No. A failed test is a finding, not automatically a verdict. Every Division 17 record should separate the testing failure from the technical failure it reveals, or fails to reveal. A cable insulation breakdown produces an insulation-resistance test failure, but an incorrect test setup can produce an incorrect result while the equipment is healthy.
It can sit with the asset (cross-referencing the relevant technical division), the test process (procedure, setup or interpretation) or the test equipment (calibration or instrument condition). Establishing which one applies prevents an incorrect verdict against the asset.
Division 17 records the full chain rather than the final pass or fail. In the cable chain, insulation deterioration leads to an insulation-resistance test failure, cable investigation, repair or replacement, retest and acceptance. The earth chain runs from electrode or connection deterioration through high earth resistance and an earth-resistance test failure to earthing corrective action, retest and acceptance. A photometry chain is also captured.
Records include test identification (failure ID, asset, system, test type, procedure reference, date, tester), test-equipment details (instrument ID, type, calibration status and validity, range and setup), test requirement (parameter, acceptance criterion, required and measured values) and failure information (category, mode, pass/fail status, extent).
Every failure receives a severity classification, plus operational-impact tagging. The classes are Critical / Safety-Critical (immediate operational or safety risk), Major / Operationally Critical (significant availability impact), Moderate (reduced performance, not yet critical), Minor / Non-Critical (limited or no operational effect), and Degradation / Intermittent / Latent (a developing or hidden fault).
A test or commissioning failure can come from a genuine system fault, a test-method error, or an out-of-tolerance instrument — real troubleshooting means understanding testing procedure and acceptance criteria well enough to know which one it actually was.
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