On high-voltage switchgear condition assessment, defect diagnostics and testing.
These papers set out the methods HVPACE uses in the field and the reasoning behind them — in enough detail to be argued with. They are written for the people who have to make the call on a piece of plant: asset managers, substation test and maintenance engineers, and switchgear manufacturers.
The most common start to a real diagnosis is not “I measured this” but “I heard that” — and an impression of a sound cannot be attached to a work order.
A phone records two kinds of evidence on one shared clock: an audio track that converts directly into analysable waveform data, and a video track that says which component was doing what at that instant. This paper sets out the four acoustic feature families worth extracting, how the video anchors a sound to a physical cause, and the three triage questions the method can actually answer — along with a plain statement of where it stops.
A ±10% pass band is 12 ms wide. The fatigue crack that eventually fractured this drive shaft moved closing time by 2 ms.
Conventional circuit breaker timing analysers verify that operating parameters sit inside an allowed range. They were never designed to detect degradation in progress, and four structural limits — end-point measurement, acceptance bandwidth, sampling bandwidth and single-shot pass/fail — put early mechanical defects out of reach. This paper works through a drive shaft that passed its last routine test and later fractured in service, then sets out how microsecond-resolution vibration measurement and baseline trending close that gap.
Polished aluminium sits at ε ≈ 0.09 and polished brass at 0.03. The field default of 0.95 is applied to both.
Infrared finds loose connections, contact oxidation, internal heating and insulation degradation without an outage — but only if the cadence, the grading and the emissivity are right. This reference covers inspection intervals for substations, lines and cables, the three-tier anomaly grading that separates monitor from act, and a working emissivity table for the surfaces actually found on power plant, with field notes on where readings go wrong.
Further papers are in preparation. If there is a measurement problem you would like covered, tell us — the series is driven by what people actually run into on site.
HVPACE is the trading name of Power Asset Condition Engineering Limited, a New Zealand-based supplier of test and diagnostic instruments and selected specialty equipment — such as cable sheath voltage limiters and other low-volume, mission-critical components — for high-voltage power systems. Backed by hands-on engineering expertise, including field-tested condition assessment techniques and AI-based signal analysis, we support customers with diagnostic guidance, methodology development and fault investigation.
If you have equipment where the standard test results look acceptable but the behaviour does not, that is the kind of problem these methods were built for.
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