Electrical Cable Very Low Frequency VLF Hipot Tester

I. Introduction:

VLF Hipot Tester is designed and manufactured for electrical equipment very low frequency withstand voltage test.

Very low frequency withstand voltage test is essentially an alternative of power frequency withstand voltage test. It is much smaller, lighter and portable than power frequency withstand voltage tester.

It is proved internationally that 0.1Hz ultra-low frequency withstand voltage test can replace power frequency withstand voltage test.

Electrical cable vlf tester can be applied for 10kV, 35kV, 300MW thermal power machine, 10kV, 35kV power transformer and other electrical equipment

II. Functions

1. Easiest to use Fully automatic microcontroller
2. Built-in printer
3. True sine wave output
4. Real-time display of actual output waveform
5. Ergonomic, menu guided, large backlit LCD
6. Storage of test results for later retrieval and print.
7. Over voltage and current protected
8. Variable frequency 0.1Hz, 0.05Hz, 0.02 Hz
9. Data of current, voltage and waveform directly sampled at HV side.
10. AC testing does not degrade good cable insulation
11. Harmful space charges are not injected into the cable insulation
12. No traveling waves are generated during testing
13. Rugged and reliable design less prone to failure from transients

III. Specifications:

1. Max voltage output: refer to following table;

2. Output frequency: 0.1Hz, 0.05Hz, 0.02Hz;

3. Measurement accuracy: 2.5%;

4. Positive and negative voltage peak errors < 2.5%RDG+0.3%FS;

5. Voltage wave form distortion:<3%;

6. Insulation resistance measurement error:<2.5%;

7. Leakage current measurement error:<2.5%;

8. Power supply:AC220V ± 10%, 50Hz/60Hz;

9. Environment temperature: 0~50°C;

10. Humidity:≤85%RH;

IV. Features:

Picutre of VLF-80KV in Serbia

• Over-voltage protection: If the output exceeds the set limit of voltage, the hipot tester will shut-down to protect itself; the actuation time is less than 15ms;

• Data of current, voltage and wave form can be directly sampled at high voltage side, so the data is real and accurate;

• Over-current protection: it is high-low voltage dual protection in the design, the accurate shut-down protection can be made according to the set value at high voltage side; If the current on low voltage side exceeds the rated current, the instrument will take shut-down protection, the actuation time are both less than 15ms;

• A high voltage output protective resistor is provided in the voltage boost body in the design and this eliminates the need of additional protective resistor connected outside;

• As a result of high and low voltage closed-loop negative feedback control circuit, the output without capacitive rise effect;

• High-voltage control part adopts innovative light control HV switching unit, control is accurate, safe and reliable;

• With colorful man-machine interface touch control plus controls modular software operating system, this vlf hipot tester is precise and intuitive;

• Multi-purpose:very low frequency tester can simultaneously measures tested objects' capacitance, insulation resistance, leakage current, and AC withstand voltage test;