The compressor is the heart of the air conditioner, and its speed directly determines the power consumed by the air conditioner. Conventional air conditioners rely on constant opening/stopping of the compressor to adjust the room temperature. This not only causes a lot of energy waste, but also often affects comfort due to quenching or sudden heat. The inverter air conditioner can work reasonably according to the ambient temperature and set value by adjusting the compressor speed to achieve energy saving and comfort. Among them, the current sensor is an important part of the inverter air conditioner, which is mainly used to measure the current of the compressor to optimize its working state.

Honeywell CSNP661 series current sensors measure current based on the Hall effect and zero magnetic field balance principle. The internal magnetic field of the sensor is always controlled at zero. The current used to balance the zero magnetic field is the primary current flowing through the conductor multiplied by the proportional coefficient of the primary line. The closed-loop current is the output of the sensor and reflects the relationship of the primary current being reduced by the secondary coil at any time. The current output can be converted to a voltage output by an external resistor.