What are the requirements specified in transformers oil specification?

Transformers oil specifications typically require the oil to have high dielectric strength, low viscosity, and excellent thermal stability. Key parameters include a minimum dielectric breakdown voltage of 30 kV, a flash point above 140°C, and a low water content (generally below 50 ppm). Additionally, the oil should exhibit low acidity, minimal oxidation stability, and good resistance to sludge formation to ensure optimal performance and longevity of the transformer.