Power Transformers

Online monitoring of dissolved gases and moisture in ​oil

Transformer Workers

Power transformers are critical components in any electricity grid. Age, increased load levels, and network disturbances all take their toll on transformers, leading to an increased risk of unpredictable faults and outages.

With online and real-time condition monitoring of power transformers utilities can keep them operating safely and with maximum efficiency, while monitoring data supports the planning of timely maintenance actions that can extend operational lifetime and prevent unexpected and costly outages.



Moisture reduces the insulating properties of transformer oil. Traditionally, oil moisture readings have been taken at periodic intervals. However, because moisture levels can change rapidly, periodic sampling is not sufficient.

Dissolved gas levels in transformer oil indicate the existence of a fault and the rate of change in these levels is used to determine its severity.

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