Transformer Oil Color and Transparency

Determination of transformer oil properties: color and transparency

What is the significance of measuring the appearance, color and transparency of transformer oil?

The color of petroleum and petroleum products depends on the content of asphalt and resin substances and other dyeing compounds in the oil. If these contents are less and more light ends, generally speaking, the color is lighter and more transparent. The color of crude oil is its general characteristic, and the degree of refining of power oil can be roughly judged from the color, that is, the degree of removal of pitch-resin substances and other coloring substances from the power oil.

New insulating oil is generally light yellow. The insulating oil produced in our country, especially the No. 45 transformer oil, has a low cut fraction and an over-refined and antioxidant process, so the appearance and color are lighter and almost colorless. Insulating oil will gradually darken in color under the influence of environmental pollution and resin produced by self-oxidation during operation. If the color changes drastically, it is usually caused by carbon generated when an electric arc occurs in the oil. Therefore, for the operating power oil, the appearance color can roughly judge the degree of oil deterioration or the internal failure of the equipment.

The transparency of oil is to observe the transparency of oil under certain temperature, oil volume and environmental conditions. If the specified temperature is lowered, the oil residue and paraffin contained in the oil will become mist and separate out, and the oil will lose transparency and become turbid. Therefore, the presence of mechanical impurities, free carbon, and moisture in the operating oil can be roughly judged based on the transparency of the oil.

Therefore, appearance, color and transparency of transformer oil is an important factor to judge the transformer oil deteriotation.

By using the transformer oil regeneration plant, the oil color and transparency will be significantly improved, as well as the oil properties.