What are the factors that affect the accuracy of current transformers?

1. Core saturation
When the primary current is too large and exceeds the rated current of the transformer to a certain extent, the core will enter a saturated state, resulting in a decrease in magnetic permeability, which will affect the measurement accuracy.
2. Secondary winding internal resistance
The secondary winding itself has resistance. If the internal resistance is too large, it will cause a voltage drop in the secondary current, affecting the measurement accuracy.
3. Electromagnetic interference
When there is a strong electromagnetic field around, additional current or voltage may be induced in the winding of the transformer, interfering with normal measurement.
4. Temperature change
The change in temperature will affect the magnetic properties of the core and the resistance value of the winding, thereby affecting the accuracy of the transformer.
5. Frequency change
If the actual operating frequency is different from the rated frequency of the transformer, it will cause measurement errors.
6. Secondary load change
The load changes of instruments, relays and other equipment connected to the secondary side may cause changes in the secondary current, thereby affecting the accuracy.
7. The installation position and method of the transformer
Installation is not firm, tilted or too close to other electrical equipment, which may affect the measurement accuracy.
8. Insulation aging
After long-term operation, the insulation performance of the transformer decreases, which may introduce leakage and affect the measurement accuracy.
9. Manufacturing process defects
For example, deficiencies in the manufacturing process such as the air gap of the core and the uneven distribution of the winding will lead to reduced accuracy.