ETL-250 移动式电气实验室，用于测试变电站设备

ETL-250 is a van-based system designed for testing electrical substation equipment. Apart from insulation withstand testing with DC (rectified) voltage up to 60 kV and ability to measure very small leakage currents, the system can be used for testing various objects with small electrical capacitance with AC voltage of up to 250 kV and measuring dielectric dissipation factor (Tan Delta) at industrial frequency. DC TESTING ETL-250 allows to carry out withstand testing of electrical insulation with DC (rectified) high voltage up to 60 kV. AC TESTING Van-based cable fault and test system ETL-250 includes high-voltage step-up transformer allowing to test various objects with small electrical capacitance with AC voltage up to 250 kV at industrial frequency (f = 50 Hz). MEASURING LEAKAGE CURRENT OF SURGE ARRESTERS A microammeter included with the system allows testing surge arresters with DC (rectified) voltage up to 60 kV and measuring the leakage current with up to 0.01 mA significance. DIELECTRIC DISSIPATION FACTOR MEASUREMENT ETL-250 system can be equipped with an optional Tan Delta module for accurate measurement of capacitance and the dielectric dissipation factor at up to 10 kV or up to 250 kV voltage of industrial frequency. Tan Delta measurement using cable test vans is most often used to assess the transformer insulators on the electrical substations.