Explain the high-voltage test transformer operation steps and usage precautions
The TQSB series special light high-voltage test transformer, developed and produced in the early stage, is a new type of high-voltage testing equipment. This series of products adopts a single-frame core-type iron core structure, with the primary winding and high-voltage winding coaxially wound on the iron core, thereby reducing leakage flux and increasing the coupling between windings. The overall structure of the product is compact, with strong versatility, and is easy to use and carry. It is suitable for power systems and power users to test the insulation performance of various high-voltage electrical equipment on site, and is an essential test instrument for power equipment testing and preventive tests.
In addition to being used for AC power frequency withstand voltage tests, the TQSB series special light test transformer can also be assembled into a DC high-voltage test device by matching with capacitors, silicon stacks, and high-voltage DC microammeters of the same voltage level and capacity, which can measure high-voltage DC leakage current.
High-voltage test transformer operation steps
1. Connect the leads according to the wiring schematic diagram, and reliably ground the transformer and control box;
2. Before the test, check whether the wiring at each part is in good contact, and check whether the voltage regulator of the control box is adjusted to the "zero" position;
3. Connect the power supply, the green indicator light turns on, press the start button, the red indicator light turns on, indicating that the transformer is energized and waiting for voltage boosting;
4. Rotate the voltage regulator handle clockwise at a uniform speed to boost the voltage, and closely monitor the instrument indications and the condition of the test object;
5. After the test, quickly reduce the voltage to zero, press the stop button, then cut off the power supply, and disconnect the test leads.
Precautions for using the special light test transformer
1. When conducting high-voltage tests, at least 2 or more personnel must participate, with clear division of labor and clear methods for mutual coordination. There must be a dedicated person to supervise on-site safety and observe the test status of the test object;
2. The test transformer and power operation box should have reliable grounding;
3. During the test, the boosting speed should not be too fast, and sudden full-voltage energization or de-energization is absolutely not allowed;
4. During the boosting or withstand voltage test, if any of the following abnormal conditions are found, the voltage should be immediately reduced, the power supply cut off, and the test stopped. Only after identifying the cause can the test be continued. ① The voltmeter pointer swings significantly; ② The smell of burning insulation or smoke is detected; ③ Abnormal sounds are heard from the test object.
5. During the test, if the test object short-circuits or breaks down, the overcurrent relay in the control box will operate. At this time, return the voltage regulator to zero, cut off the power supply, and then the test object can be removed.
6. When conducting capacitance tests or DC high-voltage leakage tests, after the test, reduce the voltage regulator to zero, cut off the power supply, and then use a discharge rod to discharge the high-voltage end of the test object or capacitor to ground to avoid the risk of electric shock from the potential stored in the capacitor.
