Can a double-flange level gauge still be used if the diaphragm on the positive pressure side is damaged?
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If the diaphragm box on the positive-pressure side of a double-flange level gauge is damaged, can I remove the capillary tube on the positive-pressure side and use the one on the negative-pressure side as the positive-pressure side, installing it at the bottom of the tank to measure the pressure there? Would that work? If that’s the case, should my transmitter’s range be set to -160KPA to 0KPA? Since my double-flange positive-pressure diaphragm cell is damaged, I plan to use the negative-pressure side to measure the pressure at the bottom of the tank, and then use formulas in the DCS to subtract this pressure from the top-of-tank pressure in order to determine the pressure difference due to the liquid level. I’m not sure if it’s okay to place the negative pressure side at the bottom of the tank for this measurement I’m hoping experts can give me some advice
Theoretically, it can be used, but in practice no one does that... If you insist on using it this way, the range should be “0–160 KPa”, with 0 as the lower limit and -160 as the upper limit (if that’s possible, as many gauges don’t allow such settings). It’s fine to use it this way if your tank isn’t sealed (but if it is sealed, I’d advise against it)... Since a “-” terminal flange is used, the resulting line will have a negative slope; therefore, either the DCS needs to invert the signal or you need to follow my settings, otherwise the 4–20 mA output won’t correspond correctly……
The first pair of flanges is used for measuring sealed containers! Have you converted the double flange to a single flange, and is your tank at atmospheric pressure? If there were no slight changes, there would be huge changes instead! 100% is possible! Also, it’s definitely not possible to use a positive-pressure capillary for this purpose! You can seal it with positive pressure! Not under pressure! Or your positive-pressure type maintains its pressure no matter how much pressure is applied! You can give it a try! But measuring the liquid level must be difficult, right?
I just need to set the DCS range to match that of the transmitter; no matter how the slope changes, I only need to be able to transmit the changing pressure to the DCS. As for inverting the value, it can be done by inverting it in the formula for calculating the differential pressure. I’m not sure if what I’m saying is correct
I wouldn’t dare to install it casually without any certainty at all; if it doesn’t work, I’ll be scolded by the technicians
The jar is at atmospheric pressure. Cutting off the positive pressure side should have roughly the same effect on atmospheric pressure and the unpressurized side of the seal. I made this change as a last resort, trying it out since I wasn’t completely sure
There is liquid inside the tank, right? If it’s a liquid, then the liquid level can be measured based on changes in pressure. You need to calculate the pressure at the highest liquid level and modify it both on-site and in the DCS.
I don’t understand what you mean. It measures the liquid, and the specification sheet indicates the pressure at the maximum liquid level. It shouldn’t have anything to do with the maximum pressure, right?
The fluctuations will be huge after the reduction! Linearity has a significant impact!
Why? Have you tried it?
We tried converting it into a differential pressure transmitter after the double flanges were damaged! But the large diaphragm box is missing! The pressure on him will be uneven, with no linear pattern! The beating is very strong! Even zero calibration cannot be completed!