VLF CR-20
In accordance with most regulations, cables and joints must be tested after installation or repair. For this test the breakdown strength of the cable is tested.
The portable VLF Test System 20 kV of Seba KMT can be used to test the cables in conjunction with the according local regulations for operating voltage levels up to 11 kV for new cables and 16 kV for aged cables at 3 µF cable capacity.
By using the patented Seba KMT 0.1 Hz Cosine Square Wave Voltage, weak and for further operation critical spots in PE, XLPE but also in paper cables are brought to a controlled breakdown very fast without causing additional damage or ageing to the cable insulation.
The weight of 50 kg make the VLF Test System 20 kV a powerful, universal and at the same time portable unit.
_ The patented change over principle in combination with
the recycling of energy stored in the cable capacity
results, in comparison to other methods, in a lower
weight, less energy consumption and much higher test
capacity.
_ The high test capacity of 3 μF permits the simultaneous
testing of all three phases.
_ The method is officially recommended by the two VDE
Standards 0276-620 and 0276-621.
_ Independent researches shows that VLF test is done
most effectively with the 0.1 Hz cosine square wave
shape compared to any other VLF wave shape or
frequency.
_ VLF is the most economic method for testing PE and
XLPE cables. DC test is not applicable for these cable
types.
_ controlled output voltage