DC Resistance Comparator

In modern industrial production,resistance is also playing a more and more important role.All kinds of resistors need to be calibrated before being put into production.In modern precision electrical measurement,resistance has become a problem that has not been solved well.Therefore,how to determine the relevant parameters of sampling resistance has become a bottleneck in the development of precision electrical measurement technology.In the international,high precision resistance comparison measurement,using two independent circuit resistance comparison circuit.The balance of the two independent circuits is equal to the voltage drop on the two resistors.The ratio of the two resistances of the bridge is inversely proportional to the current flowing through it.Mainstream manufacturers such as high DC current comparator,MI,is the current balance modulation based on the final resistance ratio.But due to the current balance of complex structure for magnetic material and process requirements are very high to a handful of the current comparator based on the structure of the manufacturing factory,and the price is very expensive,generally in the national and provincial units of measurement for a purchase amount of the authority of the resistance value transfer.Based on this situation,we put forward a new idea,designed and manufactured based on the primary side of current transformer and secondary coil under equilibrium conditions,the primary current and secondary current of a certain proportion of the unbalanced resistance bridge,using high precision ADC acquisition bridge unbalance voltage,unbalanced voltage value and standard the resistance value according to the calculation,the proportional coefficient is calibrated and the resistance value of the resistor standard,so as to realize the calibration of resistance.