Kinematic viscosity effects insulation oil

Transformer oil acts as a medium for insulation and transmission of heat,it requires choosing the right viscosity to ensure that oil played an ideal cooling effect in the long-time running, choice of appropriate low-temperature viscosity to ensure safe working of transformer stopped running when started again.Thus, United States ASTM D3487 standard requires insulation oil kinematic viscosity at 0 ° c and 100° c, as well promulgated by the International Electrotechnical Commission IEC 296 standard also provides for 40 ° c and-15 ° c (or -30 ° c,-40 ° c) viscosity requirements. Over viscosity effect heat,conversely it would decrease working security.