Transformer false oil level may be caused by the following reasons: (1) oil standard pipe block. (2) respirator plug.
(3) airway vent plug. (4) film-protected oil pillow in the refueling air is not exhausted.
Thermal aging is present in all transformer oils, both with residual oxygen in the tank and oxygen in the decomposition of the fiber. When the operating temperature is high, the oxidation process of the transformer oil is carried out faster, making the viscosity increased, the color becomes darker, mooring mud increased, tgδ value increased, the breakdown voltage drop. In addition, there is also the problem of electrical aging, with the pressure of time, the breakdown of the oil gap voltage drop. In oil-immersed power transformers, partial discharges are generated at high field strengths, which promote further condensation of oil molecules into higher-molecular-weight waxes and escape of low-molecular gases. Wax-like material accumulation in the vicinity of the high field strength of the winding insulation, blocking the oil path, affecting heat dissipation, resulting in increased gas discharge more easily.