Power Pole Transformer Test Items
During the production, installation and transportation of power pole transformer, relevant tests should also be paid attention to. The specific conditions are as follows:
(1) Voltage measurement. The regulations require that the range of voltage fluctuation should be within 5% of the rated voltage. If it exceeds this range, taps should be used to adjust the voltage to the specified range. Generally, a voltmeter is used to measure the terminal voltage of the secondary winding and the terminal voltage of the end user respectively.
(2) Determination of insulation resistance. In order to keep the transformer in normal operation all the time, it is necessary to measure the insulation resistance to prevent insulation aging and accidents. During the measurement, it is necessary to try to stop the transformer from running, and use a megger to measure the insulation resistance value of the transformer. It is required that the measured resistance should not be lower than 70% of the previously measured value.
(3) Power pole transformer temperature test. Whether the transformer is running normally or not, the temperature is very important. The regulations stipulate that the upper oil temperature shall not exceed 85 degrees (that is, the temperature rise is 55 degrees). Generally, transformers are equipped with special temperature measuring devices.
(4) load measurement. In order to improve the utilization rate of the transformer and reduce the loss of electric energy, in the operation of the transformer, it is necessary to measure the power supply capacity that the transformer can really bear. The measurement work is usually carried out during the period of the highest electricity consumption in each season, and is directly measured with a clamp-on ammeter. The current value should be 70% to 80% of the rated current of the transformer. If it exceeds, it means overload and should be adjusted immediately.
Power pole transformer testing is based on safety, and all aspects of performance must take into account the purpose of inspection. Attention should also be paid to the collection, comparison and summary of relevant data. Power pole transformer manufacturers should also pay attention to relevant protection and be responsible for the use and safety of customers!
