DC withstand voltage test is a commonly used high-voltage test method, mainly used to detect the insulation performance of electrical equipment and find insulation defects. The national standards for DC withstand voltage test mainly include the following aspects:
1. Test voltage: The test voltage of DC withstand voltage test should be determined according to the rated voltage, insulation level and other factors of the equipment under test, generally 2 or 3 times the rated voltage of the equipment under test.
2. Test time: The test time of the DC withstand voltage test should be determined according to the insulation level of the equipment under test, test voltage and other factors, and is generally 1 minute to 5 minutes.
3. Leakage current measurement: During the DC withstand voltage test, the leakage current should be measured at the same time. The leakage current should not be greater than 10 times the rated current of the device under test.
4. Judgment of test results: The test results of the DC withstand voltage test should be comprehensively judged based on factors such as test voltage, test time, leakage current, etc. If no breakdown, flashover or other phenomena occur during the test, and the leakage current is not greater than 10% of the rated current of the equipment under test, the insulation performance of the equipment under test is deemed to meet the requirements.