The distribution transformer is one of the important equipments in the power supply and distribution system for industrial and mining enterprises and civil buildings. It reduces the network voltage of 10(6)kV or 35kV to the 230/400V bus voltage used by the user. This product is suitable for AC 50 (60) Hz, three-phase maximum rated capacity 2500kVA (maximum single-phase rated capacity 833kVA, generally not recommended single-phase transformer), can be used indoors (outside), capacity is 315kVA and below Can be installed on the pole, the ambient temperature is not higher than 40 °C, not lower than -25 °C, the highest daily average temperature is 30 °C, the highest annual average temperature is 20 °C, relative humidity is not more than 90% (ambient temperature 25 °C), altitude Not more than 1000m. If it does not comply with the above conditions of use, appropriate quota adjustments shall be made in accordance with the relevant provisions of GB6450-86.
Load characteristics 1) When there are a large number of primary or secondary loads, two or more transformers should be installed. When any one of the transformers is disconnected, the remaining transformers can meet the primary and secondary loads. First, second-level load as much as possible, not too scattered.
Even with the same oil system, oils with different oil bases cannot be mixed.
Each oil system should pay attention to the characteristics of the oil at a negative temperature, such as the oil in the main body at a negative temperature, the viscosity of the oil is large, poor fluidity, poor heat dissipation. The on-load tap-changer switching switch indoor oil affects the switching process at a negative temperature and lengthens, so that the temperature rise of the transition resistor increases.
For the main oil system of an ultra-high pressure oil-immersed transformer, attention should be paid to the phenomenon of oil flow electrification, and it is necessary to prevent the transition from the charged current to the discharged current. It is necessary to control the resistivity of the oil, the oil speed of each part, and the space for releasing the charge in the oil.