continuous level measurement (CLM) is the latest technology used to measure, monitor and control the quality of a dynamic process liquid. Process fluids are highly viscous fluids which are either at or close to the defined maximum flow rate and/or pressure range within an associated vessel. The flow rate is typically set in relation to the size of the associated vessel. The flow rate is typically measured with a stoichiometric measure or with a dynamic one.
There are different methods for CLM measurement, namely: continuous level measurement of a dynamic process fluid with a low level accuracy, a fixed-point measurement of the low-level accuracy and the comparison of a fixed-point measurement against a known low level. The performance of the equipment used for continuous level measurement will depend on the type of vessel selected to perform the measurement, the type of measurement device, and the configuration of the measurement system. When a continuous level measurement is performed under the following circumstances, the results may be the same as desired. When flow is not restricted and vessel flow is unaffected by external factors, the results will be inaccurate.
The first situation in which a continuous level measurement would be inaccurate is when flow is controlled to a low value. This occurs when a large pump or other pumping mechanism is in operation. This could cause an error in the measurement of pump efficiency and flow. If this were a regular occurrence, then the instrument would have no way to distinguish between normal and abnormal pump operations.
The second situation in which continuous level measurement may be inaccurate is if the vessels are blocked by low levels of solids. When there are no solid particles or matter able to move through aqueous channels, then it is considered nearly impossible to create a measurable measurement of the density of the solids in the channel. There are a number of different types of inducers that can block the channel, including the inlet and outlet. However, without the use of an instrument, it would be impossible to tell whether or not the blockage was caused by a low level of solids. Because of this problem, the continuous level sensor was developed, and the sensor has been widely used in all kinds of situations where the accuracy of a traditional solids level sensor is not desired.
In addition to measuring the density of solids in vessels, there are many different materials that can be measured with this type of measurement device. There are some disadvantages associated with using the continuous level measurement, however. Because the measurement device must be able to detect a difference in pressure between the inlet and outlet ports of the same pressure, some differences in pressures between these ports can be undetectable by the naked eye. This problem makes the sensor unsuitable for use with many different materials that have high static capacities.
Another major disadvantage is that the continuous level measurement requires manual initiation from the instrumentation crew. In order to initiate the measuring process, a signal must first be sent up to the instrumentation department, and the operator will need to be located in the area to perform the process. There are a number of different methods that engineers have used to automate the measuring process, but they all suffer from the same problem; the signal that results from the automation process is often too weak to initiate the measuring process correctly. If this problem is significant, the automatic process may not be appropriate for the application being measured.
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