Measuring Oil Cleanliness and Detecting Contamination for Reliable Transformer Performance
The Interfacial Tension (IFT) test is performed to measure the level of polar contaminants and oxidation by-products in transformer oil, which indicates oil cleanliness and helps detect early signs of oil degradation before sludge formation, thus ensuring reliable transformer health and preventing insulation damage.
The Interfacial Tension (IFT) test measures the tension between transformer oil and water, which indicates the oil’s purity and level of degradation.
A low IFT value shows contamination or deterioration of oil, meaning the insulating and cooling properties of the transformer may be compromised.
It is usually carried out using a tensiometer, which measures the force required to detach a ring or plate from the oil-water interface.
As part of preventive maintenance, usually once a year, or more frequently if the transformer is operating under severe conditions.
It signals oil oxidation, contamination, or sludge formation, and may require oil filtration, treatment, or replacement.