The VLF AC Cable hipot tester adopts digital frequency conversion technology, single-chip microcomputer control, voltage boost, buck, measurement, protection completely automatic. Due to the full electronic, so small size and light weight, the use of large screen color touch display, clear and intuitive, simple operation, display output waveform. The design index conforms to the national standard of "General Technical Conditions of Ultra-low frequency high voltage generator".
Product features for this type of VLF hipot tester:
1.The ultra-low frequency with rated voltage less than or equal to 60kV adopts a single link structure (a booster); The ultra-low frequency of more than 60kV adopts a series structure (two booster in series), which greatly reduces the overall weight and enhances the load capacity, and the two booster can be used separately to achieve a multi-purpose machine.
2.Current and voltage data are sampled directly from the high voltage side, so the data is accurate.
3. Intelligent comprehensive protection function: there is no need to set the current and voltage protection value, the instrument can calculate the overvoltage and overcurrent protection value according to the size of the test capacity and the test voltage value, and can also protect the voltage and current mutation, so it can capture the discharge situation. The protection operation time is less than 20ms.
4.150kV high voltage line output, safe and reliable.
5.Because of the closed-loop negative feedback control circuit, the output has no capacity rise effect.
| Rated voltage | Carring capacity | Application range |
| 30kV(peak) | Automatic frequency change:0.1Hz-0.01Hz
On-load capacity:<=10µF
| Used for voltage test of cables and motors within 10KV
|
| 40kV(peak) | Automatic frequency change:0.1Hz-0.01Hz
On-load capacity:<=10µF
| Used for voltage test of cables and motors within 10KV
|
| 50kV(peak) | Automatic change frequency: 0.1Hz-0.01Hz
Load capacity: <=6µF
| Used for voltage test of cables and motors within 15KV
|
| 60kV(peak) | Automatic change frequency: 0.1Hz-0.01Hz
Load capacity: <=5µF
| Used for voltage test of cables and motors within 25KV
|
| 80kV(peak) | Automatic change frequency: 0.1Hz-0.01Hz
Carrying capacity:
<=6µF(within 50kV),
<=4µF(above 50kV)
| Used for voltage resistance test of cables and motors within 35KV
|
Output rated voltage
| 30kV-80kV
The different specifications are shown in above Table |
Output frequency
| Automatic conversion range: 0.1Hz-0.01Hz
|
Carrying capacity
| See above Table
|
AC voltage resolution
| 0.1kV
|
Voltage accuracy
| 3%
|
AC current resolution
| 0.1mA
|
AC current accuracy
| 3% |
| Voltage positive and negative peak error | ≤ 3% |
| Voltage waveform distortion | ≤ 3% |
| Conditions of use | indoor and outdoor; Temperature: -10ºC∽+40ºC; Humidity: ≤ 85%RH |
| Input power | Frequency 50Hz, voltage 220V±5%(or frequency 60Hz, voltage 110V±5%). If the micro generator is used for power supply, the frequency conversion generator should be used, and the ordinary generator can not be used, because the ordinary generator speed is unstable, which will make the boost voltage abnormal and damage the instrument. |
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Main structure of ultra-low frequency high voltage power supply(VLF hipot tester) For the VLF hipot tester with a rated voltage below 50kv, a booster is used, which is called the single-coupled ultra-low frequency, and its structure and components are described in the following figure: 
For VLF hipot tester with rated voltage above 50kv, two boosters are used in series, which is called series ultra-low frequency, and its structure and components are described in the following figure: 
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Connection method for ultra-low frequency withstand voltage test (1)
The connection method of ultra-low frequency voltage withstand test when the two-stage booster is connected in series is as follows 
(2)
Below 50kV single-link ultra-low frequency voltage test connection mode is as follows: 
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Test interface reference (Test voltage and test time can be set manually. After setting, enter the test interface, the voltage will continue to rise, and when the voltage reaches the set value, the timing will start. The voltage can be adjusted up or down by Fine up/Fine down on the screen.) 
VLF TAN DELTA TESTING 
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The following photos are the physical pictures of the 50kV VLF hipot tester 
Onsite testing 
