The transformer tester is very important for the stability and reliability of the grid voltage as an important guarantee for the safety of the power system. The transformer DC resistance tester should be far away from strong electric fields, strong magnetic fields, and high-frequency equipment. The smaller the power supply interference, the better, and the lighting cable should be used. If the power interference is still large, the instrument can be powered by the AC purification power supply. The capacity of the AC purification power supply should be greater than 200VA. When the transformer resistance tester is working, if the LCD display is disordered, all the buttons are unresponsive, or the measured value is very different from the actual value, please press the reset button, or turn off the power, and then operate again. The design and manufacture of the transformer tester, as well as the manufacturing technology and craftsmanship used in the process without good maintenance work, can easily lead to the failure of the transformer tester. When the transformer resistance tester is working, if the LCD display is disordered, all the buttons are unresponsive, or the measured value is very different from the actual value, please press the reset button, or turn off the power, and then operate again. Now people attach great importance to the transformer short-circuit fault tester. The transformer short-circuit tester can easily affect the safe operation of the power system. Previously failed testers used transformers for analysis, and a large part of the reason was caused by a transformer short-circuit tester. The tester used a transformer to avoid failure, and it was necessary to reduce short-circuit transformer testers.
1. The harm caused by the short-circuit problem of the transformer tester
When the power system is running, once the transformer tester is short-circuited, it will cause potential safety hazards in the operation of the power system. The main reason for the short-circuit of the transformer tester is that the windings of the transformer tester may be deformed under the combined action of electric field force and mechanical force.. After the transformer tester's winding is deformed, sometimes damage accidents may occur quickly.. In most cases, the transformer tester still runs for a long time. The operating time of the transformer tester mainly depends on the severity of the winding deformation and the location of the deformation. The transformer tester is prone to winding deformation or normal operation after failure. This is because, first of all, after the winding is deformed, the mechanical properties of the winding will be affected. When the winding is impacted by the short-circuit current again, it may not be able to withstand the impact of the huge power, and a damage accident will occur. Secondly, after the winding is deformed, the insulation performance of the transformer tester may change, which may cause partial discharge of the transformer tester. In this case, if the situation of the transformer tester is not discovered in time, the area of insulation damage caused by partial discharge will gradually increase in a long time, and the insulation breakdown accident of the transformer tester may eventually occur. Finally, once the winding deformation of the transformer tester occurs, it is easy to cause a cumulative effect, a vicious circle situation. The winding deformation of the transformer tester does not mean that it will cause some faults immediately, but as time accumulates, it is unpredictable what kind of consequences will occur in the future.
Solutions to prevent short circuits in transformers
2. Install an insulating heat-shrinkable sleeve on the medium and low voltage side of the transformer tester
When the transformer tester is used, the voltage level of the medium and low voltage side is very low. The outlet of the transformer tester is generally a hard bus bar, so that it is connected to the switch cabinet bus bar from the pile head of the transformer tester. All insulation heat shrinkable sleeves can be installed at the soft bus bar. Install an insulating heat-shrinkable sleeve near the connecting pile head and the wall bushing of the transformer tester.