Page 531 - Sensors and Control Systems in Manufacturing

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FIGURE 9.46 Networking of various systems in a liquid mixing operation.

Figure 9.46 shows a simple control task from chemical process
technology as an example of the networking of various systems. In a
liquid mixing plant, three different liquids—A, B, and C—are mixed
in a specified proportion. Filling is effected by three valves—A, B, and
C—and the mixture is extracted via one valve, D. Before the mixture is
removed, it is heated to a prespecified reference temperature T.
A PLC controls the valves and the mixer. The temperature of
the mixer is adjusted to the reference temperature by a two-step
controller.