Withstand voltage testing is an indispensable part of capacitor quality control, and it is also applicable to safety capacitors. Withstand voltage test, also known as withstand voltage strength test, is an important indicator to evaluate the stability and reliability of insulating materials under high electric field strength. The core of this test is to determine the maximum electric field strength that an insulating material can withstand without causing damage. In the actual test process, the safety capacitor is placed under the specified test voltage and maintained for a certain period of time. The test instrument will automatically or manually cut off the test voltage after reaching the predetermined time. If the safety capacitor breaks down during the test, that is, the current exceeds the set protection current value, the test instrument will immediately cut off the voltage and issue an audible and visual alarm to prevent further damage to the sample.
The purpose of conducting withstand voltage testing is multi-faceted. The first is to test the insulation withstand voltage capability of safety capacitors under working voltage or overvoltage conditions to ensure their safety performance in practical applications. Secondly, this test can check the insulation manufacturing or repair quality of electrical equipment and eliminate possible damage to the insulation performance during raw materials, processing or transportation, thereby reducing the early product failure rate. In addition, the test also includes checking the electrical clearance and creepage distance of the insulation to further ensure the reliability of the product.
When conducting tests, the withstand voltage tester can respond quickly when the safety capacitor breaks down, cut off the power supply and sound an alarm. This process helps determine whether the safety capacitor can withstand the specified dielectric strength test. This test can intuitively, accurately, quickly and reliably evaluate the electrical safety performance indicators such as voltage endurance, breakdown voltage and leakage current of the tested capacitor. At the same time, it can also conduct various dielectric performance tests in different forms such as power frequency, DC, surge, and shock wave in accordance with IEC or national safety standards to ensure that safety capacitors comply with relevant safety standards.