What are the common faults of Split Core Current Transformers

1. The insulating part of ct is thicker, there are wrinkles between some insulating layers, and the insulating part is loosely wrapped. In addition, the effect of vacuum treatment is not good, and incomplete impregnation leads to cavities, which is easy to cause partial discharge failure.

2. The size and arrangement of the capacitive screen are inconsistent with the design requirements. For example, the flatness of the capacitor plate is uneven, the release of the capacitor plate is less, the capacitor is broken or misplaced, resulting in the failure of the voltage equalization characteristic of the CT. Therefore, when the electric field strength of the local solid insulating surface of the current transformer reaches a certain value, it will cause partial discharge.

3. Due to unclean insulating materials or high humidity, surface discharge may occur on the CT surface. This situation is most common when the terminal lead discharges along the surface of the pad.

4. Spark discharge is caused by the suspension of the metal potential of the transformer in the warehouse and the loose connection. For example, if the supporting nut of the primary winding is loose, it will lead to the lead contact of the final wire mesh, and the shielding aluminum foil of the primary winding may be suspended, poorly welded, or even broken. These will cause the current transformer to malfunction.

5. The increase in contact resistance and local overheating of the CT are generally caused by the loosening of the grounding nut of the end screen, the loosening of the tapping nut, and the loosening of the main connecting nut, bolt and splint. In addition, improper on-site maintenance and management should also arouse attention. For example, the moisture problem of the transformer may be related to the sealing structure and sealing material of the manufacturer, but it may also be a problem of maintenance and management.