Power frequency withstand voltage testerWidely used in electrical manufacturing departments, power operation departments, research institutions, and universities to detect the electrical strength and leakage of high and low voltage electrical devices, electrical materials, and electrical components. Its output voltage and leakage current are displayed digitally. High voltage indication is sampled using a three winding transformer. Sampling of leakage current and alarm current at the high voltage end. If the leakage of the test sample exceeds the standard, an audible and visual alarm will be triggered, and the high-voltage power supply will be automatically cut off.
Experimental process:
Power frequency withstand voltage test is a test to verify the insulation withstand power frequency voltage capability of electrical equipment. During the experiment, connect the test sample to the test circuit according to the regulations, gradually increase the voltage to the rated power frequency withstand voltage value specified by the standard, maintain it for 1 minute, and then quickly and uniformly reduce the voltage to zero. If there is no breakdown or surface flashover of the insulation of the test sample within the specified time, it is considered to have passed the test. The voltage applied in the power frequency AC withstand voltage test is higher than the rated working voltage of the electrical equipment. Through this test, many insulation defects can be discovered, especially for local defects. The disadvantage is that it may cause certain damage to the insulation during the withstand voltage test. Therefore, the power frequency AC withstand voltage test can only be carried out after the insulation resistance, dielectric loss factor and other items have passed the test.
The power frequency test device can be divided into the following types according to the medium:
Oil immersed test transformer: large volume, heavy weight, large capacity, easy maintenance, high maintenance costs in the later stage; Mainstream products.
Inflatable test transformer: requires later maintenance, has good arc extinguishing performance, is lightweight, and is dangerous.
Dry type test transformer: maintenance free, lightweight, small size, reversible, high cost.
Series excited high-voltage test transformer: small capacity, low voltage, light weight, easy to transport, numerous wiring, high cost.