Magnetic balance current measuring circuit

Probe current voltage pin 420*4450 head diameter 5.0 over current current and voltage pin

As shown in the figure, the current measurement principle diagram of the magnetic balance method using the Hall element is shown. If the magnetic field generated by the measured current i2 is B1, since the B1 acts on the Hall element to generate the Hall voltage, if the voltage is converted to the current i2 by the operational amplifier and added to the feedback coil, the Hall voltage VH=0, the magnetic potential balance Then, i1N1=i2N2, that is, i2=(N1/N2)i1 If the current i2 is measured by the resistor R, a value proportional to the current i1 is obtained.