AC test system with transformer design

For testing of high voltage products and components

AC test systems with transformer design, type WP, are used to test high voltage products (for example, high voltage cables, power transformers, gas-insulated switchgears), components (bushings, arresters), and insulating materials.
They can be used in a variety of applications, such as

  • Routine testing, type testing, and in particular, wet testing
  • Indoor and outdoor testing
  • On-site testing

HIGHVOLT offers three different types of AC test systems with a transformer design depending on the specific application:

AC test system with insulating sheath transformers

The transformer is installed in an insulating sheath and is oil-cooled. Individual transformers can be connected in parallel or series to increase the current or the voltage.



  • Routine testing, type testing
  • Indoor and temporary outdoor testing
  • On-site testing


  • Space-saving design in a vertical
    cascade arrangement thanks to modular design
  • Suitable for PD measurements due to very low
    internal PD level
  • Suitable for short-lasting loads due to the test system’s short-term overload capacity



AC test system with metal tank transformers

The transformer is situated in an enclosed and earthed metal tank. This transformer is oil-cooled and can be optionally equipped with a suitable bushing (oil-to-air or oil-to-SF6).


  • Routine testing, type testing, and particularly suitable for continuous operation (for example, prequalification tests)
  • Indoor and outdoor testing (also for extreme climate conditions)
  • Wet, humidity, and pollution testing


  • Saves space in the test bay thanks to earthed metal tank enclosure
  • Very well suited for short-lasting higher loads thanks to the system design allowing continuous operation and high currents (high power)
  • Suitable for PD measurements due to low PD level
  • Extremely high test voltage reachable due to cascade design
  • Possible to test GIS components, because the metal tank transformer is often equipped with an oil-to-SF6 bushing


AC test system with GIS transformers

The transformer is designed as a GIS model and is therefore ideal for testing GIS/GIL components and switchgears.


  • Indoor testing
  • On-site testing



  • Suitable for short-lasting loads thanks to the
    test system’s short-term overload capacity
  • Ideal for PD measurements because the system is
    built entirely in GIS design
  • Compact size/minimal weight
  • Low connected load