AC test system with variable frequency

For on-site testing of GIS

Testing of withstand voltage at GIS can be performed using the AC voltage test system with variable frequency once installed on-site. The test system operates in a frequency range from 20 Hz to 300 Hz and complies with the requirements according to IEC 60517 and IEC 62271-203.


Test methods:

The WRVG G-type test system can be directly flanged to the test object. The high-voltage reactor is SF6-insulated and features a high output voltage and has a compact, lightweight design. The test system and test object become a closed system with a low PD background noise level when directly flanged. This feature makes the model ideally suited for sensitive PD measurements.

In case of the WRV M-type test system, the test object is connected to the test system via a bushing. There is an external air insulation system on the high-voltage reactor and the reactor features a modular design. Several reactors can be connected in series or parallel to achieve higher test voltages or power.


The test system can be transported in a container without taking up much space, or it can be set up on a trailer.



  • On-site testing of GIS
  • Withstand voltage testing
  • Partial discharge (PD) measurements


  • Pure sinusoidal voltage at the output
  • Low PD background noise level < 2 pC
  • IEC-compliant frequency range from 20 Hz to 300 Hz
  • Several systems can be connected in series or parallel to increase test voltage and/or power.
  • Quick and easy setup of test system
  • Maintenance-free, no moving parts

Technical parameters/system types