ZWVLF VLF Hipot Tester
The ZWVLF Series is an advanced 0.1Hz Very Low Frequency (VLF) Hipot Tester designed for high-capacitance electrical equipment.
It delivers a safe, energy-efficient, and highly precise AC withstand voltage testing solution for power cables and large generators up to 90kV.
Product Overview
The ZWVLF Series VLF Hipot Tester utilizes ultra-low frequency (0.1Hz) technology to replace bulky power frequency test transformers.
It is specifically designed to perform AC withstand voltage tests on electrical equipment with large insulation equivalent capacitance, such as XLPE power cables, power capacitors, and large to medium-sized generators.
By lowering the test frequency, this tester drastically reduces the required equipment volume and weight while providing equivalence to traditional power frequency tests, making it the internationally recommended alternative to destructive DC testing.
Functions and Value:
1. Ultra-Low Frequency Output: Utilizing 0.1Hz to 0.01Hz output reduces the necessary test capacity to 1/500 of power frequency setups, offering immense portability.
2. Pure Sine Wave Technology: Employs advanced ARM7 microcomputers and electronic switching for a highly stable waveform without harmful capacity rise effects.
3. Automated Testing Process: Features a 7-inch capacitive touch screen for simple target setting, auto-boosting, and intuitive status monitoring.
4. Closed-Loop Protection: Provides microsecond-level over-voltage and over-current protection on both high and low voltage sides for absolute safety.
5. Smart Data Management: Automatically saves up to 64 test records, featuring a built-in thermal printer and USB interface for instant reporting.
Technical Details
| Parameter | Specification |
|---|---|
| Model | ZWVLF Series |
| Output Rated Voltage | 30kV, 40kV, 50kV, 60kV, 80kV, 90kV (Peak Values) |
| Output Frequency | 0.1Hz, 0.05Hz, 0.02Hz, 0.01Hz |
| Output Waveform | Sine Wave |
| Measurement Accuracy | 1% |
| Voltage Waveform Distortion | ≤ 5% |
| Power Supply | AC 220V ± 5%, 50Hz ± 10% |
| Operating Temperature | -10°C to +40°C |
| Ambient Humidity | ≤ 85% RH |
Model Selection Guide
| Model | Rated Voltage (Peak) | Maximum Load Capacity | Key Difference |
|---|---|---|---|
| ZWVLF-30 | 30kV | 0.1Hz ≤ 0.5µF, 0.01Hz ≤ 5.5µF | Basic configuration for lower voltage |
| ZWVLF-40 | 40kV | 0.1Hz ≤ 0.5µF, 0.01Hz ≤ 5.5µF | Extended voltage range |
| ZWVLF-50 | 50kV | 0.1Hz ≤ 0.5µF, 0.01Hz ≤ 5.5µF | Suitable for 10kV cable testing |
| ZWVLF-60 | 60kV | 0.1Hz ≤ 0.5µF, 0.01Hz ≤ 5.5µF | Includes auxiliary external cylinder |
| ZWVLF-80 | 80kV | 0.1Hz ≤ 0.5µF, 0.01Hz ≤ 5.5µF | Standard for 35kV cable testing |
| ZWVLF-90 | 90kV | 0.1Hz ≤ 0.5µF, 0.01Hz ≤ 5.5µF | Maximum capacity testing |
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Parts List
| Item NO. | Max Current | Measuring Range | Main Features | Recommended Application |
|---|---|---|---|---|
| GDZR-10A | 10A | 100μΩ - 20KΩ | Portable, built-in discharge alarm | Small to medium distribution transformers |
| GDZR-20A | 20A | 10μΩ - 10KΩ | High-speed testing, heat dissipation | Medium-sized power transformers |
| GDZR-40A | 40A | 1μΩ - 2KΩ | Dual-channel measurement, high current | Large-scale power transformers |
| GDZR-40A | Three-Phase 10A | 100μΩ - 10KΩ | Three-phase simultaneous measurement | Yn-type transformers, time-saving |
Product Video
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Frequently Asked Questions
Contact our engineers for technical support and application guidance.
DC withstand voltage tests can cause severe, irreversible damage to the insulation layer of XLPE cables. The 0.1Hz VLF tester utilizes an AC sine wave, delivering a non-destructive testing method that truly reflects real operating conditions while remaining incredibly lightweight.
The load capacity varies by the selected output frequency. At 0.1Hz, it supports up to 0.5µF; at 0.05Hz, up to 1.1µF; and at 0.01Hz, it can accommodate exceptionally large capacitance up to 5.5µF.
If the test object’s capacitance is below 0.05µF, the instrument may struggle to output a perfect standard waveform. In such cases (or for higher voltage models configured with external cylinders), you simply connect the provided auxiliary compensation capacitor in parallel for normal output.
Yes. The controller is equipped with rapid-action over-current and over-voltage protections. If a sudden surge occurs due to a flashover or breakdown, it automatically cuts off the output within 10 milliseconds and initiates the discharge sequence.
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