High Voltage Testing Of Cables Pdf

For high voltage test on cables and withstand tests samples have to be carefully prepared and terminated.

High voltage testing of cables pdf.

However it provides limited knowledge of the cable condition other than whether the cable system withstood the voltage for the duration of the test or not. The cable either passes or fails the test. Testing of high voltage cables manual horizon power 1st edition february 2013 prepared by field practices safety health. High potential hi pot dc testing guidelines for medium voltage cables photo credit.

Otherwise excessive leakage or end flashovers may occur during testing. Ieee 400 3 2006 ieee guide for partial discharge testing of shielded power cable systems in a field environment. The most commonly used commercially available vlf ac voltage test frequency is 0 1 hz. However there is a risk that the cable may be understated due to a combination of lower test voltage and allowed uncertainty of the measuring circuit.

For example if you have a wire that connects two pins the high voltage will be simultaneously apply to both of those pins and the entire wire will be raised in voltage. 5 3 general it is noted that the insulating qualities of xlpe are very good and. Ieee 400 2 2013 ieee guide for field testing of shielded power cable systems using very low frequency vlf less than 1 hz. Rated 5 kv and above with high direct current voltage.

Ac high voltage test equipment design vlf operation reduces the power required to load cables which present a capacitive load. Test sets typically operate at 0 1hz. The fundamental difference between ac and dc high voltage testing is the avoidance of space charge effects. Ac is therefore recommended in most cable testing standards.

Ieee 400 4 2015. Induced stored charge in the sheath and core of cores cables adjacent to the one under test. The normal length of the cable sample used varies from about 50 cm to 10 m. Apply voltage in accordance with manufacturer s published data.

Vlf ac voltage testing methods utilize ac signals at frequencies in the range of 0 01 hz to 1 hz. Stored charge in the sheath of the cable under test. To hipot test a net you connect all of the contacts in the net to high voltage and connect all other contacts in the device to ground. Risks associated with testing of high voltage cables.

The typical high potential hi pot test is an example of a type 1 field test. In the absence of manufacturer s published data use table 100 1. Perform an insulation resistance test individually on each conductor with all other conductors and shields grounded. Perform a shield continuity test on each power cable.