TIDO® Series – Online Transformer Insulation Drying & Degassing Systems

HERING TIDO® Series - Online Transformer Insulation Drying & Degassing Systems help in getting the most out of your transformers.

The HERING TIDO® Series of online transformer insulation dry out systems dry and degasify oil filled transformers of all sizes while the transformers remain energized. TIDO® is the ideal long-term maintenance solution after an initial oil purification using HERING EOK® has been performed. This way the HERING TIDO® extracts moisture and dissolved gasses from the online transformer continuously without causing any downtime in the transformer’s operation. The HERING TIDO® online transformer drying and degassing system avoids equipment failures by stopping the underlying causes of transformer failure. The paper insulation of a transformer will degrade with time through various chemical processes leading to equipment failure & explosion risks.


The main factors influencing this decay are the moisture, temperature, and oxygen inside the transformer. A replacement or repair of the paper insulation is very costly and requires a decommissioning of the transformer as part of the overhaul. Instead, the HERING TIDO® is a non-intrusive solution which takes out both moisture(Transformer Moisture Removal) and gases from the insulation to immediately prevent the deterioration processes in the transformer.


The HERING TIDO® online transformer dryer uses a vacuum process to continually remove moisture and gas from the transformer oil. This creates a water content gradient from the wet insulation to the dry transformer oil that causes a steady removal of water from the insulation paper. The TIDO® Series allows for customization of the online transformer dry out system depending on the customer requirements.

Continuous online removal of moisture and gas from solid insulation and oil

  • Based on extensively proven technology
  • Easily installed on energized transformer
  • Temperature, moisture and transformer condition monitoring available
  • Robust design for long lifetime
  • high quality steel piping
  • All components from Western brand manufacturers
  • Numerous safety features for protection
  • Highest product quality made in Germany

Online drying and degassing your transformers with the TIDO® Series grants:

  • Benefits for new transformers – moisture content and gas content can be kept below the original factory level, thus protecting the transformer from day 1
  • Benefits for older or wet transformers – Continuous drying over several months brings down moisture & gas content to acceptable levels for extended lifetime
  • Effective moisture and gas removal for oil & paper – TIDO® ensures lowest possible moisture and gas levels within transformer oil and insulation material
  • Insulation drying for vacuum-rated and non-vacuum-rated transformers – The moisture removal takes place within the vacuum tight TIDO® equipment without affecting the transformer operation
  • No downtime due to transformer overhaul – TIDO® units can be operated on energized transformers as effectively as on un-energized transformer

Enquiry Form