Home / Current Transformers
Current Transformers
Direct measurement of current in high voltage system is not possible because of insulation problem of measuring instruments. It is also not possible to use current flowing through the system directly for protection purpose due to its high value and high insulation problem
Basic functions of current transformers are:
- To reducethe line current to a value which is suitable for standard measuring instruments, relays, etc.
- To isolatethe measuring instruments namely meters, relays, etc. from high voltage side of an installation.
- To protectmeasuring instruments against short circuit currents.
- To sense abnormalities in current and to give current signals to protective relays to isolate the defective system.
Oil filled Outdoor Current Transformers
For use in outdoor installation from 11 KV to 33 KV class. Main insulation is provided by world class insulating paper, EHV Grade Oil and good MS Metal Tanks are used along with type tested porcelain. Hermetically Sealed Oil Filled Outdoor Type.
- Single Phase Live or Dead Tank Type
- Voltage Class: 11KV .... 245KV Class
- Manufacturing as per IS & IEC standards.
- Secondary Current: 1A or 5A
- Primary Current, Accuracy Class (upto 0.2S), Burden, Short Time Current and Number of Secondary Cores as Specified.
Resin Cast Current Transformers
These are for panel mounting application upto 33KV class manufactured with latest technologies.
Epoxy resin cast CT is manufactured in compliance with IEC, ANSI, VDE, BS standards and as per customer’s specification. The windings are provided over high quality cold rolled grai n oriented steel which is annealed. The material has got low loss and high permeability. LT winding is designed as multi-layer winding. LT winding is wound on the core with additional insulation between adjacent layers. HT winding is designed in such a way that the mechanical stresses due to thermal dilation, in case of short circuit currents are not transmitted to the main insulation of the transformer.