What are the faults of the intelligent double flange differential pressure transmitter ? The intelligent double flange differential pressure transmitter is a relatively advanced intelligent instrument with strong function and high reliability. As long as it is properly maintained, it can keep them in normal operation for a long time, thus effectively ensuring the measurement accuracy and reliability of the entire control system. Sex. Intelligent double flange differential pressure transmitter products are used for a large number of liquid level measurement in towers, tanks and vessels. In the course of use, due to improper use of the method caused more failures, seriously affecting the normal use of the instrument. The author has done a lot of analysis and research on the actual faults, and found that the faults mainly have the following three categories: 1 The measured value is not displayed. 2 Does not match the safety barrier, resulting in no measurement signal or low signal in the loop. 3 Cannot communicate with DCS.

The operation of the intelligent double flange differential pressure transmitter is unreasonable: since the meter is always running at a high liquid level (above 100%), or the meter is always running at a low liquid level (below 5%), it is possible to make the meter indication super limit. Therefore, the process operator should be able to correctly determine whether the instrument is faulty or the process is improper according to the process flow and process control requirements. Therefore, it is necessary for the process personnel and the instrument maintenance personnel to closely cooperate to ensure that the process medium is within the measurement range of the instrument and avoid the operator mistakenly thinking that the instrument is faulty.

The selection of the intelligent double flange differential pressure transmitter is unreasonable: it is found that there is no migration of the double flange range, which is an important reason for the meter measurement inaccuracy and overrun. There is no range migration, so the measurement result appears outside the meter range. Measure overruns. In fact, the meter should be calculated according to the following method:

The safety barrier is not matched, so the intelligent double flange differential pressure transmitter has no output: when using the safety barrier that has not obtained the license with the smart transmitter, most of them will have such problems. The main faults are: 1 The safety gate voltage drop is too large, the whole loop voltage is lower than 16.4V, the transmitter is insufficiently supplied, and the loop cannot work, as shown in Figure 3. 2 The safety barrier is not grounded intrinsically, causing a large common mode interference signal, causing the smart transmitter to work abnormally. Taking the Z787H of P+F in the field of ketone-benzene equipment as an example, the correct connection is shown in Figure 4, but it is found that sometimes the safety barrier is not grounded, so that the transmitter has no output. 3 Although the instrument is compatible with forensics, in the case where the transformer isolated safety barrier should be selected, the intrinsically safe safety barrier is selected, so that the instrument supply voltage is insufficient, and there is no independent power supply to form a poor anti-interference ability, resulting in transmission. The device does not work properly. Therefore, choosing a suitable safety barrier for forensics is also a necessary condition to ensure that the transmitter can work normally.

Communication fault between intelligent double flange differential pressure transmitter and DCS: Generally speaking, DCS can be used to manage, configure, upload and download all smart transmitters. In the fault of the instrument, most of the faults are caused by improper setting of the internal parameters of the instrument, and the parameters of the smart transmitter are configured by communication on the DCS operation station. Therefore, their communication with the DCS is extremely important. Most of the EJA transmitters used in the plant communicate with the CENTUM-CS system. The ICS operator station can communicate with the FCS field control station and the field intelligent transmitter. The measured value, range range, self-diagnosis information and position of the transmitter. The number is configured, as shown in Figure 5. In actual production, if the transmitter and DCS communication failure, it will cause a lot of inconvenience to the instrument maintenance personnel to check the instrument parameters and instrument failure, and even the transmitter can not work normally. Article source: