Sensors based on alternative principles have been introduced as successors to conventional instrument transformers in order to significantly reduce size, increase safety, and to provide greater rating standardization and a wider functionality range.
The current sensor is based on the principle of Rogowski-coil. The sensor consists of an air-core winding, immune of any risk of saturation as it has no ferromagnetic core. It is linear over the whole measuring range. The output signal is a voltage, which is proportional to the derivative of the current. A digital integration of this voltage is carried out by IED and gives the measured current.
The current sensors are suitable for both measuring and protection purposes.
up to 0.72 kV
KECA 80 C104 1250 A, 0.5/5P400
KECA 80 C165 4000 A, 0.5/5P630
Primary air insulated switchgears (AIS),
UniGear ZS1 (UniGear Digital)
- Large dynamic range
- Small dimensions, light weight
- Only few types for whole product range
- Simplified engineering and logistics