The basic principle of AC current sensor is based on electromagnetic induction. When an alternating current flows through a conductor, a magnetic field is created around it. The sensor indirectly obtains the magnitude of the current by measuring the change in this magnetic field.

Hall current sensors mainly include two types: open loop and closed loop. Open loop Hall current sensor can directly reflect the measured current by measuring Hall potential, and is suitable for general precision current measurement. The closed-loop Hall current sensor can achieve higher measurement accuracy and stability by introducing a feedback mechanism, which is especially suitable for the occasions where the measurement accuracy is required.