JK

CURRENT TRANSFORMERS | INDOOR OPERATION

  • Hole diameters up to 300 mm
  • Various sizes available
  • Primary current up to 5000 A

Cable current transformers type JK are used in indoor switchgears. They transform high currents up to 5000 A into standardised values for meters, measuring and protection devices.

General description

Cable current transformers type JK are used in indoor switchgears. They transform high currents up to 5000 A into standardised values for meters, measuring and protection devices.

The cable current transformer is designed for installation on fully insulated medium and high voltage cables or for installation on medium and high voltage bushings. This enables a space-saving system design. Primary currents of up to 5000 A can be measured.

A specific core padding and the complete casting of all active parts in polyurethane (PUR) ensures that the magnetic properties, and therefore the class accuracy, remain constant for decades.

The standard secondary terminal enclosure permits a housing degree of protection up to IP 20. Optionally, secondary terminals can be integrated in a terminal box, providing a housing degree of protection of up to IP 65. Thanks to a wide range of geometric dimensions the cable current transformer can be adapted to customer requirements.

Applicable installation options are also available in various designs, as well as any type of installation position.

The transformers are designed according to applicable national and international standards. Designs that meet customer-specific standards are possible on request.

Advantages
JK
  • Constant class accuracy

  • Rated primary currents up to 5000 A

  • Suitable for installation over fully insulated HV and MV cables

  • Suitable for indoor applications with degree of protection IP 20 or IP 65

  • Wide range of geometric dimensions

  • Any installation position
Technical data
Type JK
StandardIEC / IEEE
Highest voltage for equipmentkV0.72
Rated power-frequency withstand voltagekV3
FrequencyHz16.7 / 50 / 60
Primary rated currentA1 - 5000
Secondary rated currentA1 / 5
Rated short-time thermal current [Ith]kA / 1s100 x In
Rated dynamic current [Idyn]kA2.5 x Ith
Accuracy class0.1-3; 0.2S; 0.5S; P; PR; PX; PXR; TPX; TPY; TPZ
Max. number of CT cores4
 
Type JK
Transformer sizeAmm230350400450
Height of unitHmm80-18080-300100-300100-300
Internal diameterDmm50-18060-250100-290100-290
Distance between screw holes at baseBmm200300350400