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Which is the best way to control the quantitative loading system - focus on microfluidic control technology

The quantitative loading system is an indispensable part of modern industrial metering and transportation, that is, the production process of liquid or solid medium into and out of the shipment automatically controls the entire filling process.
There are two common control methods for quantitative loading systems, distributed and centralized. Some customers have asked which of the two control methods is good. Our analysis is as follows:
The centralized quantitative loading system is to collect the flow meter, valve, static electricity, oil spill and other signals on the loading site through the signal cable to the PLC system in the control room, and then manage it through the upper computer.
The centralized loading system is composed of the upper computer + PLC in the cabinet. Each signal needs to pull the cable into the control room. The more cranes, the greater the construction and materials investment, and the greater the investment in the control room. The start and stop controls are indoors, and the site cannot monitor and respond, and the walkie-talkie is required. The fault point is concentrated, and once the CPU card or an I/O card fails, it will be completely discontinued. If the margin and capacity are not reserved enough, the increase is difficult; the construction is also inconvenient when expanding. All power outages must be taken to repair and replace; the operator is not easy to master and maintain.
The distributed loading system realizes the control of the field instrument and the communication with the host computer through the batch controller. The configuration of the distributed loading system is the upper machine + on-site loading instrument, and the cable enters the loading instrument on the spot, with less material and small construction. The operation is strong, the control room manages the monitoring, issues the data, and the site starts and stops according to the process, and the site can also be monitored through the loading instrument screen. The fault points are scattered, and there is a problem with one crane, which does not affect the operation of other cranes. It is easy to use and can be added to the site like stacked wood. It is possible to cut off a certain crane position without affecting other crane positions; the modular structure makes it easy to grasp maintenance.
In this way, we can see that the distributed quantitative loading system has significant advantages, so the future distributed control method will gradually replace the centralized quantitative system control method.
A clear understanding of the construction and working principle of the quantitative loading system can not only better protect the use, avoid failures that should not occur, but also make adjustments and repairs of simple problems.
After receiving the signal from the metering sensor, the quantitative loading system completes the accumulation and display in the interior, and sets the required quantitative control value inside the controller. When the cumulative value displayed by the quantitative controller reaches the When the quantitative control value is set, the quantitative controller outputs a switching amount signal. At this time, the switching signal is used to control the current interrupting device installed on the pipeline through the matching relay or the contactor, thereby achieving the effect of quantitative control.

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