Can the EJA438E pressure transmitter be used for level measurement?
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There is a methanol storage tank on which a radar was originally installed; due to the inappropriate location of the opening, there were significant fluctuations. It is planned to install an EJA438E diaphragm-sealed pressure transmitter at the bottom of the tank to measure pressure; the signal is sent to the DCS, where it is converted into a liquid level value through configuration. Please, fellow sailors, advise me on whether this is feasible. Thank you.
In our workshop, EJA210A differential pressure transmitters are commonly used in pressurized storage tanks; the transmitters are installed at the bottom and connected to the top of the tank via pressure guide tubes. It’s not clear how to use 438E to measure the liquid level of media in pressure vessels; if the vessel is open or not under pressure, using it directly should be fine
Yes. The EJA210E also measures pressure, which is converted into a level signal by the DCS. In principle, both the EJA210E and EJA438E should be fine; I’m just seeking confirmation from experts
This post was last edited by qugd on 2019-7-31 at 10:13. EJA438 is not suitable; EJA118 should be used, as methanol tanks are generally sealed and maintained at a slight positive pressure. Furthermore, as the ambient temperature fluctuates, the static pressure inside the tank will change to some extent.
I agree with what was said on the 4th floor; currently, storage tanks for flammable and toxic substances must be sealed with nitrogen in accordance with relevant requirements to prevent gas leaks. This is necessary not only for safety reasons but also as part of environmental protection requirements. There are still slight variations in the nitrogen seal pressure. Such variations can be ignored in large storage tanks, but they have a significant impact on measurements in smaller tanks, especially with light-component media. Therefore, differential pressure measurement is the best approach; for maintenance-free operation, dual flanges should be considered. Pressure tube-type differential pressure level gauges are prone to clogging! Don’t think that methanol is clean; over time, everything will get clogged.
Can’t we install an E+H cable radar? Generally, the pressure fluctuations during feeding and discharging in nitrogen-sealed tanks are quite significant
It can’t be measured. The minimum range for 438 seems to be 200 kPa, which is equivalent to a liquid level of 20 meters