HIMALAYAL - SHANGHAI - CHINA
During tangent measurement with HCL2840, high voltage output normally applies shielding end of the high voltage output line, namely the “skin”. Shielding end of the high voltage line is directly led from the high voltage end of the instrument internal test transformer, with no capacitance added. Whereas core wire of the high voltage line is connected to a sampling resistance <2Ω within the instrument in serial connection, influenced by dividing voltage during high voltage output, while measuring large capacitance test object, like 40000P, dielectric loss will increase by < 0.005%.
In conclusion, the best way for high voltage line connection is to connect with shielding only during on-site tangent measurement, connecting both core wire and shielding is also acceptable, connection to only core wire will cause slight error yet completely acceptable. During laboratorial test, it’s best to connect shielding end of the high voltage line to high voltage end of the test object