AC current transformer is one of the important equipment in power system, which is used to measure current and convert it for monitoring, measurement and protection. Choosing a suitable AC current transformer requires consideration of several factors. Here are some suggestions on how to choose an AC current transformer:

Determine the purpose: first of all, it is necessary to clarify the purpose of the current transformer, whether it is used for measurement, monitoring or protection. Different applications may require different types of current transformers.

2. Determine the rated current and transformation ratio: The rated current and transformation ratio are important factors to consider when selecting a current transformer. The rated current should match the actual current of the system to ensure accurate measurement. The transformation ratio determines the ratio of the input current to the output current, and the appropriate transformation ratio should be selected according to the demand.

3. Consider the accuracy level: the accuracy level determines the measurement accuracy of the current transformer. In the selection, should be based on the needs and standards of the system to choose the appropriate accuracy level. For systems requiring accurate measurements, a current transformer with a higher accuracy class should be selected.

4. Consider the secondary side load impedance: the secondary side load impedance has an impact on the performance of the current transformer. When selecting, the appropriate current transformer should be selected according to the secondary side load impedance of the system.

5. Consider the use environment: the current transformer should operate under specific environmental conditions, such as temperature, humidity and altitude. When selecting, these factors should be considered to ensure that the current transformer can work properly in the actual use environment.

6. Choose reliable brands and manufacturers: Choosing current transformers from well-known brands and manufacturers can ensure product quality and performance. At the time of purchase, you should choose a reputable supplier and check the product's certification and test report.

7. Consider cost and performance: When choosing a current transformer, there is a trade-off between performance and cost. The selection of the appropriate current transformer should be based on the needs and budget of the system.

Consult a professional: If you don't know how to choose a current transformer, you can consult a professional, such as a power engineer or a supplier's technical support staff, for more detailed advice and guidance.

In short, selecting a suitable AC current transformer requires comprehensive consideration of multiple factors, including use, rated current, transformation ratio, accuracy level, secondary side load impedance, use environment, brand and manufacturer, cost and performance, etc. Only by selecting a suitable current transformer can the normal operation of the system and the accuracy of the measurement be ensured.