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How does CT analyzer ensure the accuracy of current

Release Time : 2018-01-25  View Count :

The CT analyzer is an indispensable instrument for on-site verification of current transformer accuracy. The traditional current transformer test method is mainly the measurement method. Due to the limitation of the principle, the on-site verification of the current transformer is extremely inconvenient. Through continuous optimization and improvement of our products over the past 10 years, our company has adopted a new indirect test method, which is to measure the ratio and angular difference of the current transformer by measuring the internal parameters of the CT. According to the intelligent design method, combined with digital sampling technology, the DSP microprocessor is the core, and the advanced digital signal processing method is adopted. The on-site verification of the current transformer can be realized with only one instrument, which effectively solves the current mutual inductance. The problem of field testing.

The CT analyzer is an indispensable instrument for verifying the state and accuracy of the current transformer. It is to input the secondary current of the standard and the tested transformer into the instrument separately, and convert it into a voltage of the same nominal value through the internal resistance element of the instrument. Then subtract the phase difference between the two voltages, which is converted into the ratio difference and phase difference of the tested transformer relative to the standard transformer. This kind of direct comparison calibrator, because the resistance component participates in the conversion, the error is the measurement error of the calibrator, so this calibrator can only be used to verify that the accuracy of the resistance component is one order lower than the accuracy of 0.1 or less. Precision transformer.


Later, the CT analyzer developed into a differential type, which is to input the difference between the standard and the secondary current of the transformer to be input into the analyzer. The error of the internal components of the instrument is only the error of the instrument reading, that is, the error of the transformer. error. Such an analyzer can be used to characterize high-precision transformers.