Problems with double-flange level transmitters
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The diagram shows the installation location of the lower diaphragm box for the double-flange level transmitter. The installation location is incorrect; therefore, unless this location is changed, the zero point of the liquid level will definitely be inaccurate. Even when the actual liquid level in the tank is 0, there will still be a reading indicating liquid level in the section from the lower diaphragm box to the bottom of the tank. How can I remove this height value now? I’m completely confused. For example, if the distance between the two flanges is 3 meters, the medium is water, and the range is 29.58, how can I make it display the actual liquid level? I’d appreciate some guidance from those who know more about this; I’m a complete beginner. Kneeling in gratitude! ! !
Since it is connected, use a terminal that supports the dual-flange communication protocol for the migration; the measurement range remains unchanged, and the amount of migration should be determined based on the actual liquid level
How can I make the height of the paragraph below zero? Can you give an example?
Since the measurement point is below the actual 0 liquid level, a correction is needed: the original pressure value of 0 can be changed to a negative value corresponding to a certain liquid level, or in other words, a certain pressure value represents the 0 liquid level
Simply, P=ρgh=1*9.8*the length of that pipe, and that is the increase in migration amount.
It should be that when the actual liquid level is zero, there is pressure in the lower diaphragm box; however, this pressure is not useful. It is generally desired that the 0 position correspond to 0 pressure. For example, if the current pressure is 0.5 KPa, then by adjusting the parameters of the transmitter, this 0.5 KPa value is deducted. The specific procedures depend on the inverter’s manual, where the relevant parameters can be found.
In other words, it’s either the range between the two flanges plus the range for this additional distance, or it’s the range of the distance between the bottom of the tank and the upper flange plus that additional distance
If it’s worn vertically for a long time, dirt can accumulate and stick there, so be careful
For this issue, it is necessary to distinguish between the medium in the storage tank and the medium in the pressure-taking connection tube of the transmitter, as well as between the transmitter’s range and the storage tank’s range. It is also important to differentiate between zero adjustment and zero-point adjustment. Here are my steps; feel free to share your thoughts, and please forgive me if they don’t suit your preferences. 1: First, calculate the range of the storage tank: P = ρgh = 1*9.8*H. 2: Next, calculate the values on the high-pressure and low-pressure sides of the transmitter when the tank is empty: P = ρ1gh = ρ1*9.8*H1 ； P=ρ2gh=ρ2*9.8*H2; next, calculate the migration amount: P1-P2. Then, adjust the transmitter’s range when the tank is empty (i.e., adjust the migration amount): P1-P2 – (P1-P2) + P (which means zeroing the transmitter). After adjustment, when the tank is empty, check whether the transmitter’s output is 0 (if the pressure difference is 0, the output should also be 0); if it isn’t 0, zero it again. Finally, pack up the tools and go back, waiting to observe the results.