Electrical stress, normal weathering and contaminants cause insulators to lose resistivity, so it is a good idea to check for problems even if the equipment seems to be working fine. There are times that problems are already present but the insulation is still able to tolerate the fault. If the insulator fails, the damage may be catastrophic.
High potential stress verifies the reliability of insulators. However, the conventional DC hipot test isn’t suitable for electrical components already in operation. Using this testing method puts the risk of damaging the insulation of the electrical components. A safer and reliable method for testing insulation is VLF hipot. Instead of using a high DC test voltage, this test uses an alternating current with a very low frequency of 0.1 Hertz. The low frequency allows the tester to use lesser power compared to DC high potential testing.
The High Voltage VLF-65E 65 kV VLF Tester, from HVI, utilizes a dry-type, air cooled, solid state design with microprocessor control.
Its test programming, numerous output functions, wireless communications, and data retrieval are intuitive and easy to learn, as well as its PC Application software.
Portable, and built for the rigors of field use, like all HVI products, the High Voltage VLF-65E 65 kV VLF Tester‘s 0 – 65 kVac output voltage meets world standards for Acceptance testing up to 35 kV class cable and its sine wave output is suitable for using optional Tan Delta and Partial Discharge measurement systems, like the HVI TD-65E Tan Delta System.
The High Voltage VLF-65E 65 kV VLF Tester offers everything needed for fully testing cables rated up to 35 kV.