The function of the FPSO export metering automatic sampling system is to evenly sample the exported crude oil during the export of crude oil, and then the laboratory personnel will test the sampled crude oil to determine the quality of the exported crude oil. In order to ensure the stability of crude oil export and avoid the reduction of production caused by the problem of crude oil export, the sampling system which occasionally encounters problems in the process of crude oil export is studied. This paper mainly introduces the common problems that often occur in the use of the sampling switch in the sampling system. By comparing with other more stable pressure detection components, the sampling switch is changed and optimized. Under the condition of effective use of the original system architecture and functions, the micro-motion pressure switch is upgraded to a pressure transmitter. After using the pressure transmitter, some problems caused by the original pressure switch are effecting avoided, and the stability of crude oil export is improved.This upgrade idea has reference and guiding significance for other similar equipments, or other pressure switch problems.