By hvhipot 
[Keywords] Power frequency high voltage, test transformer, control box
1. When conducting high-voltage AC/DC tests, two or more personnel must participate, and clear division of labor and communication methods between each other must be established. And there is a dedicated person to monitor the safety of the site and observe the test status of the test sample;
2. The test transformer and control box should have reliable grounding;
3. During the experiment, the boosting speed should not be too fast, and sudden full voltage power on or off is not allowed;
4. If any abnormal conditions are found during the boost or withstand voltage test, the voltage should be immediately reduced, the power should be cut off, the test should be stopped, and the cause should be identified before conducting the test. ① The pointer of the voltmeter swings greatly; ② Discovering the odor and smoking phenomenon of burnt insulation; ③ There is abnormal sound inside the tested object.
5. In the experiment, if the test sample short circuits or breaks down due to a fault, the overcurrent relay in the control box will work. At this time, the voltage regulator should be returned to zero and the power should be cut off before the test sample can be removed.
6. When conducting capacitance tests or DC high-voltage leakage tests, after the test is completed, the voltage regulator should be lowered to zero and the power should be cut off. Then, a discharge rod should be used to discharge the high voltage end of the test sample or capacitor to the ground to avoid the risk of electric shock caused by the potential remaining in the capacitor.