VLF-90
The VLF-90 is a 90 kV peak sinusoidal VLF hipot test set that brings the family's highest rating…
- Maximum output voltage 0 – 90
- Output current 0 – 30
- Output frequencies 0.1 / 0.05 / 0.02 / 0.01
VLF-30
30 kV Very Low Frequency (VLF) AC Hipot Test Set
Lightweight two-piece 30 kV peak VLF hipot for routine and maintenance withstand testing of shielded power cables.
Maximum output voltage
0 – 30
Output current
0 – 30
Output frequencies
0.1 / 0.05 / 0.02 / 0.01
Load rating at 0.01 Hz
≤ 5.5
Measurement accuracy
± 3 % of reading
Controller + HV tank
4 + 20
Overview
Technical Specifications
| Specification | Value | Unit |
|---|---|---|
| Output AC voltage (peak, sinusoidal) | 0 – 30 | kV |
| Output current (peak) | 0 – 30 | mA |
| Output frequency | 0.1 / 0.05 / 0.02 / 0.01 | Hz sinusoidal |
| Duty cycle | Continuous | |
| @ 0.1 Hz | ≤ 0.5 | µF |
| @ 0.05 Hz | ≤ 1.1 | µF |
| @ 0.02 Hz | ≤ 2.2 | µF |
| @ 0.01 Hz | ≤ 5.5 | µF |
| Measurement accuracy | ± 3 % of reading | |
| Voltage positive / negative peak error | ≤ 3 % | |
| Controller unit weight | 4 | kg |
| High-voltage tank (booster) weight | 20 | kg |
| Design | Two-piece split system (controller + HV tank) | |
| Power supply | AC 220 V / AC 230 V, 50/60 Hz, or AC 120 V, 60 Hz | |
| Operating temperature | −10 … +50 | °C |
| Storage temperature | −20 … +70 | °C |
| Humidity | ≤ 85 % RH | |
Key Features
Compact split design for field mobility
Control unit of 4 kg plus a 30 kV high-voltage tank of 20 kg — one of the lightest split systems in the family, easily handled by two technicians.
True sinusoidal VLF waveform
Polarity reverses every half cycle like power-frequency AC, giving a space-charge-free stress appropriate for XLPE and EPR insulation.
Four output frequencies
0.1 / 0.05 / 0.02 / 0.01 Hz let the operator trade test time for reach on high-capacitance cable sections.
30 kV peak with 30 mA output
Delivers full rated voltage across the load rating up to 5.5 µF at 0.01 Hz on a continuous duty cycle.
Automatic IEEE 400.2-2013 interpretation
The 7-inch touch-screen controller judges results against IEEE 400.2 criteria automatically.
Built-in thermal printer & storage
Results are saved internally and printed on site, producing field documentation without an external PC.
No PC required
Complete test setup, execution and reporting are handled locally from the touch screen.
Applications
Routine & maintenance withstand testing
Periodic VLF proof testing of shielded distribution cable insulation.
Post-installation / post-repair verification
Confirming cable circuits and joints after installation or repair work.
Contractor handover checks
Quality verification of new cable installations by contractors and utilities.
Space-restricted sites
Substation bays, manholes and tunnels where a truck-mounted test set cannot reach.
Industrial & utility plants
Cable reliability and preventive-maintenance programs.
Frequently Asked Questions
What VLF test voltage should be applied to a cable under test?
IEEE 400.2 recommends a test voltage related to the cable's phase-to-earth rating (U0), typically 1.5 to 3 times U0 depending on whether the test is acceptance or maintenance and on cable age. Confirm the target voltage for your specific cable class before testing.
Why is a sinusoidal VLF test preferred over DC proof testing for XLPE/EPR cables?
DC testing can leave space charge in cross-linked (XLPE/EPR) insulation that may cause premature failure later. A sinusoidal VLF waveform reproduces the operating AC stress with polarity reversal each half cycle, giving a more realistic and safer test for polymer-insulated cables.
Can the VLF-30 be operated without a computer?
Yes. The 7-inch touch screen controls the full test sequence, interprets results against IEEE 400.2-2013 and prints them on the thermal printer, so no external PC is required in the field.
How is the VLF-30 transported and set up?
It is a two-piece split system — a 4 kg controller and a 20 kg high-voltage tank. Connect the two with the supplied HV lead and the return/earth lead, then program the test from the touch screen.
Downloads
Related Products
VLF-80
The VLF-80 is an 80 kV peak sinusoidal VLF hipot test set for field testing of medium- and…
- Maximum output voltage 0 – 80
- Output current 0 – 30
- Output frequencies 0.1 / 0.05 / 0.02 / 0.01
VLF-60
The VLF-60 is a 60 kV peak sinusoidal VLF hipot test set for medium- and high-voltage shielded power…
- Maximum output voltage 0 – 60
- Output current 0 – 30
- Output frequencies 0.1 / 0.05 / 0.02 / 0.01
VLF-50
The VLF-50 is a 50 kV peak sinusoidal VLF hipot test set designed for AC withstand testing of…
- Maximum output voltage 0 – 50
- Output current 0 – 30
- Output frequencies 0.1 / 0.05 / 0.02 / 0.01