What’s the recommended transformer oil filtration frequency for mid-voltage units?

For 35-110 kV transformers, filtration should be done at least once every 2-3 years, depending on load cycles and environmental conditions. Fluidex systems allow both offline and online filtration, so you can maintain oil condition without interrupting power supply. Regular servicing improves BDV, removes moisture, and ensures the oil stays within operational standards. Many companies now schedule filtration as part of annual preventive maintenance.