Outdoor Oil/Paper CTs and VTs

Pfiffner manufactures a wide range of outdoor instrument transformers to the latest International and Australian standards from 24 to 550kV using oil/paper technology.


Their current and voltage transformers are:

  • available with either silicone composite insulators or with optional porcelain insulators upon request
  • have a high level of safety against explosion hazards
  • hermetically sealed
  • manufactured using aluminium casings

The high voltage current transformers consist of various head types in different sizes and one hairpin type with Viton membrane. All oil-filled head types have metal expansion bellows to withstand higher thermal loads. The CTs can be produced with flat or round primary connectors.


Pfiffner also manufactures a range of oil/paper insulated capacitive voltage transformers up to 550kV in both.


A resistive/capacitive voltage divider (RCVD) is also available for high precision measurement of voltage and harmonics with no ferroresonance susceptibility. This product allows accurate high level quality of supply monitoring from the HV networl.


Pfiffner’s produces oil / paper combined instrument transformers, providing a space saving solution for combined current and voltage measurement. The design incorporates current transformer cores in the top head housing and voltage transformer windings in the base housing.


Savings in space, civil, external cabling and associated construction costs make the combined CT/VT a usefulalternative to discrete units.