In order to ensure the normal operation of the transformer, the following tests should be carried out frequently.
1. Temperature test. Whether the operating state of the transformer is normal, the temperature level is very important. The regulations stipulate that the temperature of the wire must not exceed 85C (ie, temperature rise 55C). Generally, transformers are equipped with special temperature measuring devices.
2. Load determination. In order to improve the utilization rate of the transformer and reduce the loss of electrical energy, in the operation of the transformer, the power supply capacity that the transformer can really bear must be determined. The measurement work is usually carried out at the peak of electricity consumption in each season, and it is directly measured with a clamp ammeter. The current value should be 70-80% of the rated current of the transformer. If it exceeds, it indicates overload and should be adjusted immediately.
3. Voltage measurement. The regulations require that the voltage fluctuation range should be within ±5% of the rated voltage. If it exceeds this range, the tap should be used to adjust so that the voltage reaches the specified range. Generally use a voltmeter to measure the secondary coil terminal voltage and the terminal user terminal voltage.
4. Determination of insulation resistance. In order to keep the transformer in normal operation at all times, the insulation resistance must be measured to prevent insulation aging and accidents. During the measurement, the transformer should be stopped, and the insulation resistance value of the transformer should be measured using a shaker. It is required that the measured resistance is not less than 70% of the previously measured value. When the shaker is selected, the low-voltage coil can use a voltage level of 500 volts.
ECKO with a mature testing system including all the above tests. We make sure every transformer is tested strictly and 100% past before delivery.