Transformer Dissolved Hydrogen (DGA) Tracker

The widely used limit is 100 ppm (IEEE C57.104 condition levels — H₂ above ~100 ppm moves a transformer out of 'condition 1' and into investigation territory (limits vary with transformer class and history)). Set a warning at 50 ppm so parts and labour are ready before the alarm. Your OEM manual or internal procedure overrides the generic figure.

Not necessarily — a single absolute means little without history. An old, hard-worked unit can sit at 80 ppm stably for a decade; a new unit reaching 80 ppm in six months is generating gas fast. Resample in 30 days: stable ≈ benign legacy gassing; rising ≥10 ppm/month ≈ active fault — order the full gas suite and apply Duval/Rogers ratios to identify it. This tracker exists precisely to hold that history.

At least 4–6 spread over a meaningful fraction of the asset's life, with a fit R² of about 0.7 or better. Two points always make a perfect line — that is curve fitting, not condition monitoring. Keep measurement conditions (load, temperature, location) consistent.

It is the standard first approximation for steady-state degradation, and it is deliberately conservative to act on. Many failure modes accelerate near the end (bathtub curve), so treat the projected date as the latest acceptable intervention date, not a promise.

Entirely in your browser's localStorage on this device — nothing is uploaded to any server. Export or note critical values elsewhere if you need a permanent maintenance record shared across a team.