Current transformers, along with voltage or potential transformers, are instrument transformers. Instrument transformers scale the large values of voltage or current to small, standardized values that are easy to handle for measuring instruments and protective relays. The instrument transformers isolate measurement or protection circuits from the high voltage of the primary system. A current transformer provides a secondary current that is accurately proportional to the current flowing in its primary. The current transformer presents a negligible load to the primary circuit.
Testing of Current Transformers (CTs) and Potential Transformers (PTs) is crucial to ensure their proper operation and accuracy in electrical measurement and protection systems. Here's a detailed overview of the testing procedures and considerations for both types of transformers:
General Considerations for Both CTs and PTs:
- Safety: Always adhere to safety protocols when testing, especially with high-voltage equipment.
- Calibration: Ensure all testing equipment is properly calibrated for accurate measurements.
- Documentation: Record all test results and compare them with manufacturer specifications for compliance and performance verification.
- Maintenance: Regular testing and maintenance help prevent issues and ensure the reliable operation of CTs and PTs.