False liquid level alarm.
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Our company uses Hilscher systems, and a few days ago we noticed an incorrect level alarm. Upon inspection, it was found that the liquid level had not reached the alarm setting; I’m not sure what the reason is
Your question doesn’t seem to be clear enough – are you asking whether an alarm is triggered when the indicated value in the system does not reach the set value, or when the value displayed by the system reaches the alarm threshold while the actual liquid level on site does not reach that displayed value? If the reading of the level transmitter does not match the actual conditions at the site, it is necessary to consider whether the parameters set for the level transmitter are consistent with the actual conditions there. If the on-site conditions match those of the transmitter, the system alarm is incorrect; in such cases, replace the relevant card, or check the alarm wiring and settings.
Can’t view the historical curve? Is it possible that the data collection time for your historical database is longer than that of DCS, so the excessive alarm values at a certain moment were not recorded, leading you to mistake it for a false alarm? If that doesn’t work, just check the transmitter and conduct a DCS static test.
It can be divided into on-site alarms and process alarms. If there is no excess at the on-site level, then there is a problem with the process; check your instruments, communication system, and power supply system:D
Check your transmitter; it’s probably the one that has a problem:D
1. Set the data collection interval for historical data to around 1 second. 2. Observe for a period of time; if alarms continue to occur, check whether there are any sharp changes in the curve. 3. If the sudden change occurs within a few seconds, there is likely a problem with the DCS card. If it’s a matter of a few minutes, check issues related to the gauge.
It’s very likely to be due to the DCS; signal interference can cause jumps.