Series WKO

Closed loop current transformers


WKO current sensors work in accordance with the proven compensation principle and are suitable for measuring direct, alternating and mixed currents.

The primary current generates a magnetic flux, which is compensated by an internal secondary coil. The current is evaluated by an electronic circuit and a Hall sensor. The secondary compensating current is a precise representation of the primary current to be measured.

According to: 

  • EN50178
  • EN50121, EN55011
  • IEC61869-1, IEC61869-8, IEC61010-1
  • UL94-V0 – UL Norm: all parts are UL-listed

Unique Selling Point

  • Measurement of direct, alternating and mixed currents
  • Very high precision and short response time
  • Broad frequency spectrum and low temperature drift
  • Very good linearity and overcurrent resistance
  • No additional losses in the measuring circuit (DC to 150 kHz)
  • Current output for lengthy transmission lines
  • High-quality UL listed insulating materials (e.g. UL94-V0)
  • Safe electrically isolated primary and secondary circuits
  • Robust housing designs (for horizontal/vertical mounting)
  • Variable connections, e.g. clamps, plugs, flat-cable plugs or cables
  • Wide range of housings with various push-through openings

Technical Data

  • Accuracy: better than 1%
  • Ambient temperature:  -25°C … +70°C
  • Storage temperature: -25°C … +85°C
  • Primary rated current : 25 – 2000 A
  • Frequency range : 100000 – 200000 Hz