The current used by the precision shunt in practical applications does not exceed 80% of the rated current. Although the precision of the precision shunt is small, it can work with a large current. For the voltage of the precision shunt, we use a millivolt voltmeter to measure. However, I need to pay attention to the following points during actual use.
In many cases, precision shunts and measuring voltage instruments are used together to directly measure AC and DC currents, calibrate the current functions of various calibrators, and support calibration of high current transconductance amplifiers. At present, some precision shunts have very low phase shift. This feature is very important for AC power measurement, especially for non-sinusoidal waveform measurements. The magnitude of the current signal can be obtained in the power quality analyzer and the current sampler of the digital power meter. Phase.

The physical structure and precision of the components inside the precision shunt ensure that its frequency response is very flat, the resistance value is very stable and accurate, with excellent low self-heating power factor and low temperature coefficient, which can be used to directly measure current from DC. Up to 100kHz, DC current accuracy is 20 ppm, AC current accuracy is 23 ppm, and precision shunts from some manufacturers can reach 1PPM, 5PPM, 10PPM. Therefore, the precision current measurement can be directly converted according to the shunt resistor value, and it is not necessary to use the traditional complicated AC/DC conversion method. 


In addition, some precision shunts have a nominal voltage output of 0.8V. Compared with other 45/75 mV shunts, the output voltage is high, which greatly improves the signal-to-noise ratio. It is very convenient to use a precision voltmeter or other measuring instruments. The resistance corresponding to the current of 100A is 8mW, and the current range is 10mA as the resistance is increased to 80W. In addition, the 1mA shunt has a battery-powered buffer amplifier that drives the output voltage, allowing the 800W shunt resistor to interact with the measurement device with minimal interaction. 


In addition, the precision shunts are currently produced by each manufacturer. In the case of the development and update of the production technology department, the working efficiency, voltage, operating temperature and resistance accuracy of the precision shunt are greatly improved. The device has been well tested in smart meters and new energy vehicle applications, and various battery management systems and smart meters are widely used in precision shunts.