The idea of on line filtering conceived as we have 4 nos 31.5 MVA similar transformers of 20 years old with following test measurements. Until year 2002-08 IR reading (at 5 kV)of these transformers were above 5000 Mohm which is comparable to commissioning values. In 2003-05 it drops to 200...
Velcon Systems too supplied on line transformer dry out system with patented filtration product. But the product is recommended for removal of dissolve water and different filter element is recommended for cost effective removal of free water. When analysing oil for moisture content (say using...