Vlf Cable Testing

The device under test must withstand a vlf very low frequency ac voltage for a preset testing time without flashover.

Vlf cable testing.

Perform the test as instructed to make best use of vlf technology. The vlf test instrument should be solidly grounded before connecting up any cables. 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. Vlf cable testing is the cutting edge technology for proof testing of fully operating medium voltage cables and the detection of faulty ones.

Making them useful especially for field testing where transport and space can be issues. Vlf cable testing very low frequency is a technique for testing of medium and high voltage mv and hv cables. 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. The major application is for testing solid dielectric cable per ieee 400 2 followed by testing large rotating machinery per ieee 433 1974 and occasionally for testing.

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. Vlf systems are advantageous in that they can be manufactured to be small and lightweight. Because the inherent capacitance of a power cable. Vlf cable testing makes use of ac voltages in a frequency range of 0 01.

If a vlf test is too low in voltage and or too short in duration more harm than good may result. During the test cables are subjected to a test voltage significantly higher than what they experience during normal operating conditions. When vlf withstand testing cable the proper test voltage and time duration are critical for the success of the test. In the first step a go no go statement is sufficient.