How is a traditional current transformer test typically performed?

A traditional current transformer test is primarily conducted by applying high current on the primary side of the transformer. This approach allows for the evaluation of the transformer's performance under actual operating conditions. When high current flows through the primary winding, the transformer will produce a proportional secondary current based on its turns ratio. By analyzing this relationship, technicians can assess various operational parameters, such as accuracy and saturation characteristics.

This method is critical for ensuring that the current transformer functions correctly within its specified range, providing accurate measurements for protective relays and metering applications. Additionally, testing on the primary side fosters a better understanding of how the current transformer will behave during normal operation and protective events.

Testing the secondary side with high current or measuring voltage across the core are not standard practices for current transformer evaluations, as these methods do not provide the same insights into performance and accuracy under nominal operational conditions. Similarly, insulation testing focuses on the dielectric integrity and does not specifically assess the current transformer's operational effectiveness or calibration.