The measured size of the current selection of the current transformer rated current ratio

According to the measured size of the current selection of the current transformer rated current ratio, which is to make the current transformer primary rated current is  electric transformer  than the measured current. This is the current transformer in the selection of the most important point to note. Also pay attention to the size of the rated voltage of the current transformer, the choice and use it to line voltage to adapt.
And supporting the use of AC current transformer should be selected 5 amp ammeter range. Usually  mcb circuit breaker  with current  air circuit breaker  supporting the use of this type ammeter scale is based on the current transformer primary winding current rating scale. This marked the ammeter should be equipped with a current transformer rated current transformer ratio, in the selection of this meter, it must be and the corresponding supporting the use of current transformers.