Micro current Transformers play the role of current transformation and electrical isolation. In the power generation, power transformation, transmission, distribution and use of electricity lines, the size of the current is relatively wide, from a few to tens of thousands of Ann will exist.
In order to facilitate our measurement, protection and control needs to be converted to a relatively uniform current, in addition, the voltage on the line is generally relatively high, if the direct measurement will appear to be very dangerous. For pointer-type ammeter, most of the two currents on the miniature current transformer are ampere (such as 5A, etc.). And with regard to digital instrumentation, the sampled signal is MA class (0-5V, 4-20ma, etc.).
The two-time current on the miniature current transformer refers to the MA class, which mainly plays the role of bridge between the large transformer and the sampling. Micro Current Transformers will also be referred to as "instrument current Transformers". (And when it comes to "instrument current Transformers" there is a meaning that the multi-current used in the laboratory will be more than the precision current transformer, generally used to expand the instrument range.)
About this transformer and transformer similar, but also will be based on the principle of electromagnetic induction work, transformer transformation is the voltage and current transformer transformation is the current.
And when it comes to the winding (the number of turns) of the micro current transformer connected to the measured current, it is called a winding (or it will be called the original winding and the primary winding), and the winding on the measuring instrument (the number of turns is N2) is called the two-time winding (or will be called the side winding, secondary winding). The current ratio of the primary winding current I1 and the two winding I2 on the miniature current transformer will be called the actual current ratio K. When the micro current transformer works under the rated current, the current will also be called the current transformer rated current ratio, should be noted with KN.
The function of this transformer is to convert the primary current with a larger value into a relatively small two-time current by a certain variable ratio.