Shaanxi Sefon Electrical Equipment Co., Ltd.

Oil-immersed transformers use oil as the main insulation means of transformers, and rely on oil as a cooling medium, such as oil-immersed self-cooling, oil-immersed air cooling, oil-immersed water cooling and forced oil circulation. The main components of the transformer are iron core, winding, oil tank, oil pillow, respirator, explosion-proof pipe (pressure relief valve), radiator, insulating sleeve, tap switch, gas relay, thermometer, oil purifier, etc. The oil-immersed transformer silicon steel sheet layer, due to long-term immersion in the transformer, oil can penetrate into it, and the transformer oil has elasticity and acts as a buffer, so the oil-immersed transformer has low noise.

The working principle of the oil-immersed transformer is based on the principle of electromagnetic induction, and the voltage conversion is achieved through the interaction between the iron core and the winding. ‌ When alternating current passes through the primary winding (main coil), an alternating magnetic field will be generated in the iron core, and this magnetic field will pass through the secondary winding (secondary coil), thereby generating an induced electromotive force in the secondary winding. If the secondary winding is connected to a load, a current will be formed to complete the power transmission.

All series of products are suitable for 10kv/12kv/20kv/24kv/35kv power distribution systems, which can be used for residential areas, commercial streets, industrial and mining enterprises, urban and rural power grid transformation, etc.
High-rise buildings: Due to the special power supply needs of high-rise buildings and large power loads, there are also high requirements for power supply quality and stability. The use of oil-immersed transformers can provide stable power support and ensure the safety of people and equipment. In addition, when the quality of survival power is high, the oil-immersed transformer has overload capacity and can cope with instantaneous or periodic load peaks.
Industrial and mining enterprises: The production equipment of industrial and mining enterprises not only consumes a lot of power, but also wastes a lot of power during operation, which requires the power supply system to meet high load and high stability requirements. Oil-immersed transformers can be used as voltage stabilizing devices for industrial and mining enterprises to effectively solve the problems of power fluctuations and voltage fluctuations and ensure stable operation of equipment.
Urban rail transit: Urban rail transit is a high-standard and high-demand modern transportation tool, and the power supply has high requirements in accordance with national standards. Oil-immersed transformers can withstand high loads and high frequencies in such extreme environments, meeting the needs of urban rail transit equipment.
Urban and rural power grid transformation: Oil-immersed transformers are suitable for urban and rural, industrial and mining power grid transformation, and are more suitable for combined transformers and prefabricated transformers for substations.

Temperature and humidity: Oil-immersed transformers are suitable for ambient temperatures ranging from -25°C to 40°C, with a maximum daily average temperature of 30°C, a maximum annual average temperature of 20°C, and a relative humidity of no more than 90% (at 25°C). For transformers used outdoors, the minimum temperature is -25°C; for transformers used indoors, the minimum temperature is -5°C.
Altitude: The operating altitude of oil-immersed transformers is ≤1000 meters. Special design is required for altitudes exceeding 1000 meters.
Fire safety: When installing and using oil-immersed transformers, attention should be paid to fire safety. For example, the fire separation distance between a transformer with an oil volume of more than 2500kg and an oil-filled electrical device with a volume of 600kg-2500kg shall not be less than 5 meters. If the fire separation distance between two adjacent oil-immersed transformers does not meet the installation requirements, a fire wall or a fireproof water curtain on the top of the fireproof partition wall is required.
Power supply voltage: The waveform of the power supply voltage should be similar to a sine wave, and the power supply voltage of a three-phase transformer should be approximately symmetrical.

S13-M series fully sealed 10KV (12KV) (20KV) (24KV) (35KV) series three-phase oil-immersed power transformers
Product Overview:
- Low loss, 30% lower than S11 type transformer loss
- Low no-load current and no-load loss.
- Unique structural design and material selection. S13 transformer has strong overload capacity
- Compact structure and small footprint: The structural design of S13 transformer makes the product structure more compact and the layout more reasonable.
- Environmental protection and energy saving: S13 transformer is a green energy-saving equipment that is beneficial to environmental protection and is the latest product promoted and used in urban and rural power grid technical transformation projects.
- In summary, S13 transformer has been widely used in the power industry for its low loss, low noise, strong overload capacity, compact structure and environmental protection and energy saving.
- Mainly used in distribution networks, industrial and mining enterprises and civil building power supply and distribution systems.

Table 1 10KV class 30KVA~2500KVA non-excitation voltage regulating distribution transformer

Table 2 20KV Class 50KVA~2500KVA Non-excitation Voltage Regulating Distribution Transformer

Table 3 35KV class 50KVA~2500KVA non-excitation voltage regulating distribution transformer

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