Control Power Transformers

General Details

Control Power Transformers

Control Power Transformers for indoor use in Medium Voltage Switchgear applications. 5 kV to 34.5 kV Voltage Class, with 60 to 150 kV BIL.

Control Power Transformers are Vacuum Cast using Epoxy Resin, offering horizontal and vertical mounting on selected models. Typical applications include medium voltage(MV) switchgear, and medium voltage(MV) motor control & generator/transformer neutral grounding.

A Current Transformer (CT) is a type of transformer that is used to reduce or multiply an alternating current (AC). It produces a current in its secondary which is proportional to the current in its primary.

Current Transformers, along with voltage or potential transformers, are instrument transformers. Instrument transformers scale the large values of current to small, standardized values that are easy to handle for measuring instruments and protective relays. The Instrument transformers isolate measurement or protection circuits from the high voltage of the primary system. These units provide a secondary current that is accurately proportional to the current flowing in its primary, presenting a negligible load to the primary circuit.

These units are the current sensing units of the power system and are used at generating stations, electrical substations, and in industrial and commercial electric power distribution.

Advantages are that the units can measure high current easily, high electrical isolation, simple construction, and easy maintenance and installation.

The Crompton Instruments product range represents one of the largest product offerings of power measurement, control, and protection instrumentation, for switchgear and generator set manufacturers, panel builders and OEMs.


  • 5 kV to 34.5 kV Class
  • 5 to 75 kVA Single Phase
  • 15 to 150 kVA Three Phase
  • 60 to 150 kV BIL
  • Horizontal & Vertical Mounting on some Models
  • Indoor Designs for use in Medium Voltage Switchgear
  • Vacuum Cast using Epoxy Resin



  • Designed to meet C57.12.01


  • RU E148498 on selected models


CPT3-60-0.5 Control Power Transformer

CPT3-60-0.5 Control Power Transformer

  • RU E148498 on selected models