Vlf Cable Testing Procedure Pdf

These numbers result from many years of vlf field use and research.

Vlf cable testing procedure pdf. Ieee guide for field testing of shielded power cable systems using very low frequency vlf 1. During the test cables are subjected to a test voltage significantly higher than what they experience during normal operating conditions. Ieee 400 3 2006 ieee guide for partial discharge testing of shielded power cable systems in a field environment. There are no rules of thumb to be used.

Vlf testers are smaller and more practical than ac testers but output the same amount of power as a 50 hz mains device. 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. This combination of size and power makes very low frequency cable testing perfect for testing longer sections of cable and apparatus. Overview this guide provides a description of the methods and practices to be used in the application of very low frequency vlf high voltage excitation for field testing of shielded power cable systems bach b1 1 and 2 2.

The cable tests described below are to be carried out after. It is commonly used in the industry for acceptance testing prior to energizing the cable and for maintenance testing programs. Ieee guide for field testing of shielded power cable systems using very low frequency vlf less than 1 hz. The test measures the insu lation resistance between the phases and or between phase and ground.

It is intended to detect deterioration of the system and to check the serviceability so that suitable maintenance procedures can be initiated. Insulation resistance testing purpose. Approximately 12 of cables fail during the test and cable repair can then be done in a planned manner. Download pdf contact hvi testing summary.

Insulation resistance testing is a non destructive test procedure. Vlf cable test voltages and time durations are set by ieee standard 400 2 2013. High voltage withstand tests are used in conjunction with partial discharge measurements on solid dielectric cable and accessories within manufacturing plants to ensure the quality of completed cable system components from mv to ehv. Ieee 400 4 2015.

Reduction in cable life. The benefits of vlf maintenance testing regular routine maintenance testing of aged cables has been demonstrated to reduce the chance of unscheduled failure to approximately 10 of the failure rate that might be encountered without such testing. Vlf testing uses very low frequencies as part of an ac cable maintenance routine.