Why should the transmitter of the orifice flowmeter be grounded?

One of the issues that needs to be paid attention to when using many flow meters is that the transmitter of the flow meter should be grounded, which can well avoid the problem of interference. Why is there such an effect? ​​Why should

the transmitter of the flow meter be grounded?

1. When the fluid cuts the magnetic lines to generate a flow signal, the fluid itself is used as the zero potential, a positive potential is generated on one electrode, and a negative potential is generated on the other electrode, which changes alternately. Therefore, the midpoint C of the converter input terminal must be at zero potential with the fluid, so as to form a symmetrical input loop.

2. Since the output signal of the transmitter is very small, in order to improve the anti-interference ability of the instrument, the zero potential in the input loop must be grounded, with the earth potential as the zero potential. At the same time, the grounding of the measuring tube shell of the transmitter can play a shielding role and reduce the electromagnetic field interference of the outside world and the excitation system itself. Therefore, in order to make the ZR-LG-K orifice flowmeter better measure and ensure the measurement accuracy, the transmitter must be grounded. The transmitter with a grounding electrode has many characteristics. The measuring tube of the transmitter is directly connected to the fluid, which plays a role in ensuring the zero potential of the fluid. The transmitter's anti-interference ability is improved, and the structure is simpler than the transmitter with a grounding flange, saving materials. However, after the transmitter is equipped with a grounding electrode, the reliability of the electrode seal and the processing technology of the transmitter are required to be higher. (end)