The step-up transformer runs hotter, harder and closer to its limits than any other unit on site. That is why GSU partial discharge monitoring belongs on the main transformer.
An anonymized 220 kV field record: online DGA acetylene monitoring caught 0.29 µL/L at dawn, escalated through 1.93 and 2.55, and the laboratory confirmed 2.99 µL/L eleven hours later.
Anonymized converter-station records at ±660 to ±800 kV: online DGA saw 0.07 µL/L acetylene 32 h before a fast climb, matched laboratory results to A1-class accuracy, and tripped a unit on a ≈2 µL/L per week criterion.
Three anonymized AC-substation field records — a 1000 kV reactor spare and two 500 kV transformers — show trace acetylene at 0.15–0.8 µL/L caught by online laser-PAS DGA, matched by the lab, and acted on before failure.
gsu transformer replacement is a long-lead, costly call. A CIGRE 2026 case study shows how DGA and dissolved hydrogen guide repair-vs-replace.
DGA monitoring for transformer fleets means screening every unit with hydrogen first, then confirming on critical assets. A tiered strategy keeps spend proportional to risk.
DGA monitoring prevents catastrophic transformer failure by catching incipient faults weeks before symptoms appear. Hydrogen sensing closes the blind zone between lab samples.
Data center main transformers run at high load 24/7; an unplanned failure can cost more than the asset. Online DGA protects the single point of failure.
Industrial main transformers face outage losses far above asset value. Learn how online DGA and managed monitoring protect continuous production.
Nuclear power plant DGA must meet QA, metrological traceability, and integration needs. Learn how online DGA complements periodic offline sampling.
