For some vortex street sensors, the diameter selection or the process conditions change after the design selection, resulting in the selection of a large specification after Z. therefore, the actual selection should select the diameter as small as possible to improve the measurement accuracy. For example, a vortex street pipeline is designed to be used by several equipment. Sometimes some process equipment are not used, resulting in the reduction of the current actual use flow. The actual use results in the oversized diameter of the original design selection, which is equivalent to increasing the lower limit of measurable flow. The indication of process pipeline can not be guaranteed when the flow is small, but can still be used when the flow is large. It can be combined with the readjustment of parameters to improve the indication accuracy.

2. Installation reasons

In terms of installation, the length of the straight pipe section in front of the sensor is not enough, which affects the measurement accuracy. For example, the straight pipe section in front of the sensor is obviously insufficient. Because fic203 is not used for measurement and is only used for control, the current accuracy is equivalent to degraded use.

3. Influence of temperature on measurement

The influence of temperature change on the geometric size change of the measuring body is composed of two parts: one is caused by the change of the width of the vortex generator, and the other is caused by the change of the inside diameter of the pipe. To eliminate this effect, the K coefficient is usually corrected.

4. Reasons for parameter setting direction

The instrument indication is incorrect due to parameter error. The parameter error makes the calculation of the secondary instrument full-scale frequency wrong. The similar full-scale frequency makes the indication inaccurate for a long time. The actual full-scale frequency is large, and the calculated full-scale frequency makes the indication fluctuate in a wide range and cannot be read. The inconsistency of parameters in the data affects the final determination of parameters. This problem can be solved by recalibration and mutual comparison.