Toroidal Ring Type CTs
A range of ring type current transformers suitable for primary currents from 1A-5000A with 1A or 5A secondaries. This standard range of measuring and protective current transformers is available as resin coated or tape wrapped.
Suitable for measuring or protective applications, available in standard Class 1, Class 0.5 and Class 5P10. Other accuracy class available on request such as Class 0.2, Class 0.5s, Class10 P10, Class 10P20 etc.
We also design to customer specification on request.
- Primary currents from 1A - 10000A
- Measuring or Protective types.
- Base or busbar mounting.
- Choice of sizes to customers specification.
- Conforms to IEC44-1, IEC 185, BS7626 and IEC 61869-2.
- Rated system voltage 0.72 / 3kV.
- Ambient temperature range -5°C to +50°C.
- Frequency range 50-60Hz (400Hz available on request).
- Insulation Level, 3kV (50Hz for 1 minute.
- Continuous current, 1.2 x rated current.
- Short-term thermal current (Ith), 60 x rated current.
- Dynamic current (Idyn), 2.5 x Ith.
Where possible the instrument is remote from the CT, the VA imposed by the length of the connection wires should be taken into consideration.
The graph opposite outlines the effect of connection wire length on VA.
For example, a 400/5A CT with 2 primary turns passed through the centre, will provide an actual ratio of 200/5A