Abstract:In order to improve the lightning protection safety of petrochemical instrument,the design of lightning proof grounding system,This paper proposes a leakage protection and excitation inductance of the gain distribution and the detection control method of grounding system design method,the current Maxwell theorem based on the analysis of electromagnetic field of petrochemical instrument,lightning protection and grounding,double operational amplifier LM358 amplifier as the core of Petrochemical Instrument lightning protection grounding system circuit design,including the design,filter design,AC amplifier the design of detector and DC amplifier design,using 8 order high pass filter in the receiver design(S3529)in parallel,improve the lightning protection and grounding system output amplifier performance,the system debugging and circuit testing,the results show that the design of petrochemical instrument grounding lightning protection in the system,the stopband attenuation greater than 51dB,with the high pass filter and low-pass filter,better performance of the lightning signal,to better protect the safety of Petrochemical Instrument.