Temperature of oil-immersed transformers
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This post was last edited by Cu Hua Yi Su on 2018-5-11 at 16:05. There is a 10kV oil-immersed power transformer in the factory area; recently, almost no equipment has been operating on the low-voltage side. However, the oil temperature in the upper part of the transformer was measured to be 50 degrees Celsius. Since the transformer is quite old, it’s also impossible to see clearly through the oil sight glass on the oil conservator. Is this normal?
Your transformer is likely of the S9 series; it’s not the S7 series, right? And it’s not made with an aluminum core, either, is it? When the transformer is unloaded, its temperature is close to the ambient temperature; if the ambient temperature is 25 degrees, a reading of 50 degrees on the transformer’s oil level gauge indicates a clear abnormality. It is recommended that you touch the exterior of the transformer to check whether its surface temperature is also high, so as to determine whether the oil level indicator is giving incorrect readings or if the transformer’s temperature is indeed high. If the temperature is truly high, the transformer needs to be tested and inspected to identify the cause of the problem.