Stock Photo of Inflatable High-Voltage Test TransformerWorking Principle:
Power input is connected to an operation box equipped with overcurrent automatic trip and zero-position interlock device to prevent sudden pressurization. The voltage is regulated by an auto-transformer and then input to the primary winding of the test transformer. According to the principle of electromagnetic induction, a voltage amplitude proportional to the turns ratio between the secondary (high-voltage) winding and the primary winding is obtained - power frequency high voltage. This power frequency high voltage can be rectified by a high-voltage silicon stack and filtered by a voltage-stabilizing capacitor to obtain DC high voltage, whose amplitude is twice the effective value of the power frequency high voltage.
Precautions:
1. When conducting high-voltage tests, at least 2 or more personnel must participate, with clear division of labor and mutual communication methods. A dedicated person should supervise on-site safety and observe the test status of the sample;
2. The transformer and control box should be reliably grounded;
3. During the test, the voltage increase speed should not be too fast, and sudden full-voltage energization or de-energization is strictly prohibited;
4. During voltage increase or withstand voltage tests, if any of the following abnormal conditions are found, immediately reduce the voltage, cut off the power supply, stop the test, and investigate the cause before resuming. ① The voltmeter pointer swings significantly; ② There is a smell of burning insulation or smoke; ③ Abnormal sounds from the tested object.
5. During the test, if the test sample is short-circuited 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 only then can the test sample be removed.
