The measurement value of the Rosemount electromagnetic flowmeter is too low
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Our factory has a split-type Rosemount electromagnetic flowmeter; the transmitter belongs to the 8712 series, while the sensor is part of the 8711 series. Recently, we have noticed that the measurement values are significantly low. The installation method has not been changed, and the configuration parameters have been checked and found to be correct. We have also conducted routine inspections on both the transmitter and the sensor with no suspicious findings. We are now in a difficult situation; please, experts, help us!
Check if there are any deposits on the electrodes; this is a likely possibility, and cleaning them will improve the situation.
What do you mean by \"clearly on the low side\"? What is it being compared to? I would like to ask how long this watch has been in use, whether it needs maintenance, and also that all the electrical requirements must be met!
Thank you! This set of meters has been in normal use for nearly two years; the sensor electrodes appear clean and undamaged, and they have been cleaned as well. The reason given for the significantly low measurement values is that a process pipeline equipped with a 2-inch flow meter was used to deliver liquid into a tank with a capacity of 10 cubic meters, and the liquid would overflow within 20 minutes or so. Yet, during that time, both the transmitter’s display and output values indicated around 4 cubic meters per hour, whereas it was possible to see from the outlet of the process pipeline that the actual flow rate was higher than that.
It’s possible that the insulation of the electrodes is poor, and over time the insulation layer gets damaged.
Thank you to my friends for their advice; the problem has been solved.
It is suggested that the original poster share the solution and the cause of the fault; reading this feels like watching a mystery movie with no ending. It itches in my heart. There is another scenario: if the medium is viscous, there will be interference from the fluid itself, and this can generally be addressed by adjusting the excitation frequency. The flowmeters of the 8732E model are available in two frequencies: 5HZ and 37HZ; other models seem to have frequencies of 5HZ and 30HZ.
I suggest showing everyone the results of handling the issue
I’m sorry, but I’m still completely confused as to how to solve this problem; fundamentally, I don’t think my approach aligns with this phenomenon at all. In other words: first, use the elimination method to rule out as many possible causes of this phenomenon as possible; finally, the only option left was to replace the sensor’s signal cable with one from the transmitter, and that resolved the issue. Can someone help me explain why this is the case?
I’ve encountered the same problem, and I plan to handle it in exactly the same way as you did. I didn’t realize that someone else had already used this approach. Thank you
Could it be that the cable connection is poor?