Vacuum pressure transmitter
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Our company uses a distillation process, and the column has four pressure measurement points from top to bottom; these points are used primarily for measuring vacuum. Currently, pressure transmitters of type 3051 are used for this purpose, and the range of these transmitters is set to (-101.3 – 101.3 KPa) using a HART device in an atmospheric environment. All signals are fed into an 8-channel pressure monitoring device for observation. The company requires that the vacuum level be accurate to within 100 Pa, yet the actual error in vacuum measurement is around 1–2 KPa. Could it be that the transmitters are not functioning properly? Are there any transmitters that can directly measure absolute pressure?
Before use, the transmitter must be calibrated or verified with a standard vacuum gauge; it cannot be adjusted arbitrarily.
Is your model the 3051CG? Are the errors all around 1-2 KPa? The vacuum pressure seems unable to reach -101.3, right? It can only go up to 98, I guess. Go and check the transmitter to see if its accuracy meets the requirements. Alternatively, you can replace it with a 3051CA gauge pressure transmitter to directly measure and display the absolute pressure; give that a try
Can the range be set to a smaller value? Accuracy is related to the measurement range
Since it is for measuring vacuum, there is no need to consider conditions above atmospheric pressure; a gauge pressure transmitter will suffice. The measurement range is determined based on the process requirements, and that is how our vacuum distillation tower is designed.
I’m not entirely sure; I don’t know if it’s possible to use a vacuum gauge for direct measurement. Vacuum gauges are commonly used in vacuum ovens to measure vacuum levels with high precision, but they also have a certain range of measurement. It depends on what range you need for your application
Use a gauge pressure transducer； Before use, be sure to calibrate it; calibration should be performed within the range for which measurement is to be taken, otherwise the measurements will not be accurate. A precision of within 100 Pa is required; commonly used transmitters, once calibrated, work without any issues. The measurement range of vacuum gauges on ordinary vacuum furnaces is typically between 100 Pa and several negative powers of 10 Pa (from 10² to 10⁻²). Such high levels of vacuum are not required in the chemical and petrochemical industries. From 10^5 Pa to 10^(-10~-12) Pa, such high levels of vacuum can only be achieved by combining several units, such as various vacuum pumps in series.
For a range of 0–400 KPa, is it feasible to use the HAITR table to shift the range to -101.3–101.3 KPa?
The range set for my current transmitter is not suitable; there is a discrepancy between the vacuum value measured by it and that obtained using a gauge pressure tester. For example, at -101 KPa, the gauge pressure indicated by the gauge pressure tester is 300 Pa. I’m not sure if such a comparison is valid
The range set for my current transmitter is not suitable; there is a discrepancy between the vacuum value measured by it and that obtained using a gauge pressure tester. For example, at -101 KPa, the gauge pressure indicated by the gauge pressure tester is 300 Pa. I’m not sure if such a comparison is valid