What is the upper limit temperature for oil-immersed type transformer?

2025-10-23 15:16:02

Oil-immersed type transformer are essential equipment in the power system, and their main function is to convert electrical energy from one voltage level to another. However, during operation, Oil immersed transformer generate heat, and if the temperature is too high, it may have a serious impact on the insulation performance and service life of the transformer.

The upper temperature limit of a transformer is usually set by the manufacturer, and this value depends on various factors such as the design, materials, and manufacturing process of the transformer. Generally speaking, the upper temperature limit of a transformer should be within its rated operating temperature range. For oil immersed transformers, their rated operating temperature range is usually -40 ℃ to+50 ℃, while the rated operating temperature range for Oil immersed transformer is usually -30 ℃ to+120 ℃.

However, this is only the theoretical upper limit of temperature. In reality, the temperature of the transformer should be maintained at a slightly lower level than the rated operating temperature. This is because when the temperature of the transformer exceeds its rated operating temperature, its insulation performance will decrease, which may lead to serious accidents such as short circuits or fires. In addition, excessively high temperatures can accelerate the aging process of transformers and shorten their service life.

To ensure the safe operation of transformers, temperature sensors are usually installed inside to monitor their operating temperature in real time. Once the temperature exceeds the set threshold, the alarm system will be activated to remind operators to take timely measures to reduce the temperature. These measures may include increasing the speed of the cooling fan or reducing the load on the transformer.

Overall, although the upper temperature limit of the transformer is set by the manufacturer, in actual operation, we should try to maintain the temperature of the transformer at a relatively low level to ensure its safety, stability, and continuous operation.