Vlf Cable Testing

Vlf cable testing very low frequency is a technique for testing of medium and high voltage mv and hv cables.

Vlf cable testing.

Connection setup for a vlf cable connecting a vlf test instrument to a cable refer to ieee 400 2 for safety guidelines. Vlf systems are advantageous in that they can be manufactured to be small and lightweight. This kind of test is suited for testing high capacitance loads such. Very low frequency vlf withstand testing is the application of an ac sinusoidal waveform generally at 0 01 0 1 hz to assess the quality of electrical insulation in high capacitive loads such as cables.

Hv test lead ground cable figure 4. If a vlf test is too low in voltage and or too short in duration more harm than good may result. In the first step a go no go statement is sufficient. The device under test must withstand a vlf very low frequency ac voltage for a preset testing time without flashover.

Vlf testing is not only used for testing solid dielectric cable any application requiring ac testing of high capacitance loads can be tested using very low frequency. Because the inherent capacitance of a power cable. Perform the test as instructed to make best use of vlf technology. Vlf cable testing is the cutting edge technology for proof testing of fully operating medium voltage cables and the detection of faulty ones.

Vlf cable testing makes use of ac voltages in a frequency range of 0 01. A very low frequency vlf withstand test is an ac withstand test usually carried out at a frequency between 0 1 hz and 0 01 hz. During the test cables are subjected to a test voltage significantly higher than what they experience during normal operating conditions. Making them useful especially for field testing where transport and space can be issues.