When is a portable transformer oil filtration machine used?

Portable filtration machines are used when oil condition needs improvement without removing the transformer from service or without a full oil replacement. Typical triggers include elevated moisture, low BDV, high particle count, or after a repair that opened the oil system to air. They are also used during commissioning, after transportation, and after a spill or leak repair to restore cleanliness. Depending on the equipment, the unit may provide fine filtration, vacuum dehydration, and degassing. For severe oxidation or sludge precursors, regeneration with adsorbents may be required rather than simple filtration.