There is a discrepancy between the on-site magnetic flap level gauge and the DCS for the liquefied gas tank – what could be the reason?
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Someone asked me about the discrepancies between the on-site level gauges of the spherical tank and those in the DCS, and what could be the reasons for such differences.
The DCS is accurate; there is some error on-site, and it’s difficult to obtain readings when some magnets only flip halfway
If the magnetic flap doesn’t get stuck, it should provide relatively accurate readings. Is the liquid level in the DCS determined by differential pressure or some other principle? The differential pressure is related to the issue of selecting the density for liquefied gas.
There is gas BOG on top.....................
There are many reasons for the discrepancies between the on-site level gauge and the level gauge in the DCS. These can be caused by large differences in the readings provided by the on-site level gauge and those from the DCS, changes in density under different operating conditions, or leaks in the pressure transfer tubes..........
It’s likely that the display panel is inaccurate; there should be no problem with the remote sensing function, as it operates by sensing the magnetic float inside the conduit – the level reading indicated by the remote sensor will correspond to the position of the magnetic float.
There is a discrepancy between the on-site level gauge and the level gauge in the DCS; first check the on-site gauge, which provides the most direct reading, and if there are no issues then check the remote one
When a magnetic float level gauge is installed outdoors, debris can affect the rotation of the magnetic column; however, long-distance signal transmission should not be affected by such factors.
The on-site display of the magnetic flap and the indication from the DCS are not based on the same measuring mechanism.
The original poster didn’t ask clearly: what is the float in use at the site, and what kind of gauge is used for remote transmission? How many remote transmissions? What type of instruments are they respectively, servo radars or something else? How large is the error? Is the deviation large occasionally or constant? Do the readings of the several remote sensors match? Only by clearly stating the problem can it be analyzed and solved, right, original poster?
Liquefied gas is a volatile liquid at normal temperature and pressure; the cause of errors is the presence of vapor in the vapor pipe, along with liquid (differential pressure measurement method)