In order to facilitate the field use of active zero-flux current sensors, an adaptive device is developed. It can be used as an accessory product of current sensor. The internally integrated power supply module can provide a high stability and low ripple working power supply for most existing mainstream sensors. It can lead out the secondary current of the sensor through a special interface. The secondary current is subjected to I-V transformation, digitization and other subsequent processing. It is not only convenient for measurement application, but also improves the measurement accuracy of the current sensor.