A VLF (very low frequency) hipot is an AC output tester but with an output frequency of 0.1 Hz or lower, rather than 50/60Hz. Although the frequency is very low, it is still an alternating current with polarity reversals every half cycle. At 0.1 Hz output, rather than 60Hz, it takes 600 times less current and power to apply an AC voltage to a capacitive load, like a long cable.
There is no better way to verify the AC integrity of a cable than to hipot it with AC voltage. VLF hipots are used to provide a go/no-go, or pass/fail, voltage withstand test. It can also be used as the voltage source for diagnostic cable testing.
I&E Central represents High Voltage Inc’s VLF Hipots for cable testing. Highlights include:
- The preferred method for proof testing cables and other high capacitance specimens
- Recommended per IEEE 400.2. Proof tests cable without degrading insulation.
- Models from 28 kV to 200 kV (28 kV unit shown in photo)
- Test Frequencies from 0.1 Hz down to 0.01 Hz AC
- Used stand-alone or as a voltage source for tan-delta or partial discharge testing
Please note that I&E Central represents High Voltage Inc in NY state only. If you are outside of NY State, please contact us and we’ll get you in touch with your local distributor.