Features The impulse voltage generators / series L are the main component of impulse voltage test systems, series L (see Data Sheet 3.10), ranging from 100 kV to 1200 kV cumulative charging voltage. They are designed for testing high-voltage equipment of power systems with lightning impulses (LI: 1.2/50 µs) and switching impulses (SI 250/2500 µs) according to the IEC standard 60060-1 (IEEE St.4). The maximum charging voltage is 100 kV per stage with a maximum energy of 5 kJ per stage. With 12 stages, maximum output voltages of 1150 kV (LI) and 900 kV (SI) can be generated in the no-load case. The impulse voltage generators can be modified for carrying out a variety of special tests, e.g. on transformers, impulse current testing of surge arresters as well as EMP tests of electrical equipment. The chosen modular system enables a very variable application in industries as well as in laboratories for research and education. The circuit of the impulse voltage generators is the Marx multiplier circuit. The impulse capacitors, arranged in the stages of the impulse voltage generator, are charged in parallel with DC voltages up to 100 kV against earth potential and, in order to generate impulses, connected in series by spark gaps. For the adjustment of the front time and time to half value of the test impulse, the generator stages comprise front resistors and tail resistors. A short discharge loop guarantees low internal inductances and smooth voltage shape. The impulse voltage generator is constructed in five-column design. All of these columns are made of glass-fiber reinforced plastic support; three of them serve as supports for the impulse capacitors in the generator stages. All necessary front and tail resistors are arranged between one of the three columns and a fourth column. At the fifth column the fixed sphere gaps and the charging resistors of each stage are arranged. The movable sphere gaps are fixed together at a vertically arranged insulating bar, which can be horizontally moved for adjustment of the gap distance with the help of a motor drive on earth potential. The five insulating columns are placed on a common sectional steel base which is designed either as stationary or as a mobile type.