What causes fluctuations in the level gauge?
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The level gauge of one of our liquefied gas tanks is showing continuous fluctuations on the DCS, and this has been going on for several days. The data on the DCS comes from a field magnetic flap level gauge with remote transmission functionality; it’s not clear whether the problem lies with the gauge itself or with the magnetic flap level gauge The cause has never been identified. . . Hey You, please help.
A stable 4-20ma current signal applied behind the cabinet safety barrier can be used to determine whether the issue lies with the card or with the field primary meter
Reply to 2# sizang: Thank you, I’ll try to figure out what the problem is. .
Reply to 1# pdf1314: Are surge protectors installed on the instruments at your site to prevent lightning damage? We used to experience fluctuations as well, but those fluctuations stopped after we removed the surge protectors.
Reply to 1# pdf1314: If it’s only the DCS that shows fluctuations, it’s likely a problem with the wire numbers; you can first check whether the connections are secure~
The interference from the motor is also quite severe; is the shielding in order?
Adjust the damping and give it a try! ! ! ! !
Test the output separately; to measure liquefied gas using the side flip valve, it is necessary to close the inlet and outlet valves, at which point the magnetic flip valves will move up and down
Test the output separately; to measure liquefied gas using the side flip valve, it is necessary to close the inlet and outlet valves, at which point the magnetic flip valves will move up and down
The gasification phenomenon of liquefied gas is quite severe; if the magnetic flap level gauge does not have proper gas and liquid chambers in its main conduit, the float will exhibit oscillation, which affects the transmission output (affecting accuracy). Of course, this analysis is limited to the gauge itself – it’s also possible that there is a problem with the DCS. It’s best to conduct a step-by-step analysis; this is for reference only!
It seems that the magnetic flap level gauge has more problems; the remote transmission unit contains a large number of reed switch resistors, resulting in poor reliability