Power frequency electromagnetic interference test and analysis of the rail weighbridge pressure sensor

From the field test found that the data of rail weighbridge pressure appear sine wave whose frequency is 50Hz. In order to solve this engineering problem, we studied the electromagnetic compatibility of rail weighbridge pressure sensor. First of all, we analyzed the principle of pressure sensor. Then, we tested the field strength of signal lines and power cord, testing the voltage between cable shielded layer and the earth. Through the theoretical analysis and calculation of field intensity around the signal cable, we found that cable shielded layer as interference sources cause interference to the signal conductor. Circuit model analysis of shielding layer caused by parasitic capacitance coupling between the core mechanism of deformation compression case study analyzes the shielded cable for signal transmission. Through theory and simulation analysis, it is concluded that the shield potential changes, conductor and shield interference between the change of the coupling capacitance of conductor.