QDTB® Transformer
K

Kidney Loop Filtration

Diagnostics & Maintenance

An online oil purification system continuously filtering transformer oil through a side-loop circuit to remove moisture and particles.

Kidney loop filtration continuously processes transformer oil through a portable or permanently installed side-loop filter unit. Removes moisture, particles, and oxidation products without taking the transformer out of service.

Stages: particulate filtration (1–10 micron), vacuum dehydration (reducing moisture to <10 ppm), clay/adsorbent treatment (removing acids and sludge). Monitored by inline breakdown voltage meters.

Extends oil life and prevents fault gas generation. Critical for EHV transformers.

QDTB recommends kidney loop filtration for all transformers above 50 MVA and offers permanently installed units.

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