What kinds of tests should the oil-immersed transformer perform during operation?
In order to ensure the normal operation of the oil-immersed transformer, the following tests should be carried out frequently: temperature test. Whether the operating state of the oil-immersed transformer is normal or not, the temperature is very important. The regulations stipulate that the upper oil temperature must not exceed 85C (ie, the temperature rises to 55C). Generally, oil-immersed transformers are equipped with special temperature measuring devices. Load measurement. In order to improve the utilization of oil-immersed transformers and reduce the loss of electrical energy, in the operation of oil-immersed transformers, it is necessary to determine the power supply capacity that oil-immersed transformers can truly bear. The measurement work is usually carried out during peak hours of each season and is directly measured with a clamp-type ammeter. The current value should be 70-80% of the rated current of the oil-immersed transformer. If it exceeds the load, it should be adjusted immediately. Voltage measurement. The regulations require that the voltage variation range be within ±5% of the rated voltage. If this range is exceeded, taps should be used to adjust the voltage to the specified range. The voltage of the secondary coil terminal and the terminal voltage of the end user are generally measured by a voltmeter. Insulation resistance measurement. In order to keep the oil-immersed transformer in normal operation, the insulation resistance must be measured to prevent insulation aging and accidents.
When measuring, try to stop the oil-immersed transformer. Use the shaker to measure the insulation resistance of the oil-immersed transformer. The required resistance is not lower than 70% of the previously measured value. When the shaker is used, the low-voltage coil can be used as 500 volts. Voltage level. It is proved by theory that the voltage ratio of the primary coil to the secondary coil of the oil-immersed transformer is related to the ratio of the turns of the primary coil to the secondary coil, which can be expressed by the following formula: primary coil voltage / secondary coil voltage = primary coil turns / secondary The number of turns in the coil indicates that the more turns, the higher the voltage. Therefore, it can be seen that the secondary coil is less than the primary coil, which is a step-down oil immersed transformer. The opposite is a boost oil-immersed transformer.
