** I. Preparation**
1. **Environmental Inspection**: Ensure that the test environment is free of safety hazards, such as flammable and explosive materials, slippery ground, unstable power connections, etc.
2.
2. **Equipment Preparation**:
- **Test Transformer**: Confirm that the high-voltage test transformer is in good working condition, the wiring is not loose, and the grounding is reliable.
- **Measuring Instruments**: Calibrate the withstand voltage tester (such as megohmmeter, oscilloscope, ammeter, etc.) to ensure that its accuracy meets the requirements.
- **Protection devices**: Check whether the discharge ball gap, current limiting resistor, overcurrent protection device, etc. are normal.
3. **The transformer under test**:
- **Appearance check**: ensure that the transformer appearance is not obvious damage, no oxidization of the pins, fracture and other phenomena.
- **Cleaning treatment**: clean up the transformer surface dust, ensure that the electrode contact parts are clean, to avoid affecting the test results.
**Two, withstand voltage test steps**
1. **Primary and core withstand voltage**:
- **Connecting the test line**: in accordance with the prescribed wiring, the output of the high-voltage test transformer and high-frequency transformer connected to one end of the primary winding and the magnetic core.
- **Boosting test**: Gradually increase the voltage to the specified value according to the specified boosting rate and hold it for a period of time (e.g. 1 minute).
- **Recorded Data**: Observe and record the current value, voltage value, and whether there is any discharge phenomenon.
- **Reduce voltage and disconnect**: Slowly reduce the voltage to zero and then disconnect the test line.
2. **Primary and secondary withstand voltage**:
- **Connect the test line**: Adjust the wiring, so that the output of the high-voltage test transformer is connected to the other end of the primary winding and one end of the secondary winding (or according to the requirements of the test to choose the appropriate terminal).
- **Repeat the above process**: perform the voltage withstand test according to the same boosting rate, holding time and recording requirements.
3. **Voltage withstand between secondary and core**:
- **Adjust the wiring again**: connect the high-voltage test transformer to the other end of the secondary winding to the core.
- **Performing the Withstand Voltage Test**: complete this part of the Withstand Voltage Test in accordance with established procedures.
**III. Evaluation and Recording of Results**
1. **Compare Standards**: Compare the measured data with the voltage withstand requirements in the product specifications or relevant industry standards to determine whether the requirements are met.
2. **Abnormal situation handling**: If there is an abnormal discharge, abnormal increase in current, etc. during the testing process, it is necessary to immediately reduce the voltage and find out the reason, and it may be necessary to repair or re-test the transformer.
3. **Record and report**: Record the voltage value, current value, test result (pass/fail), test date, tester and other information of each test, and form a voltage withstand test report.
**Four, follow-up processing**
- For the high-frequency transformer that passes the withstand voltage test, it can be assembled or put into use in the next step.
- For the transformer that fails the test, it is necessary to rework, replace parts or scrap according to the cause of the problem, and analyze the cause of the failure to improve the production process or design.
Please note that the actual operation should strictly follow the laboratory safety regulations and equipment manual, wear personal protective equipment, and take additional safety measures when necessary. In addition, specific test sequences, voltage levels, hold times, and other parameters may vary depending on product specifications, manufacturer's instructions, or relevant standard requirements.