Ionization flame detectors are primarily used for flame detection in gas industrial burners. They are developed based on the unidirectional conductivity of flames and the ionization reaction phenomena present in the combustion process. Due to the presence of positive and negative ions in the flame, a weak current is generated in the external circuit when an electric field is applied to the flame. The detection circuit in the ionization flame detector is high when a flame signal is present; low when there is no flame signal, the probe shorts, or there is severe leakage between the probe and the body, serving as a control signal. After appropriate amplification, it drives the corresponding actuator to achieve control or alarm output.