Abstract
Mixing liquid control system based on PLC is designed, which takes three kinds of liquid
mixing control for example. It need to mix three kinds of liquid accorded to certain proportion,
and output the liquid when it achieve a certain temperature after the motor stir. Then it form
circulation state
Design liquid mix control system need that its act continuous and all devices’ relevance
each other. For different state and control corresponding output so that achieve a control cycle
from join the first liquid complete mixing liquid. The design mainly introduce and explain the
making process, which based on liquid mixing control system, including hardware component
and software choose (design scheme, flow, request, ladder-diagram, external connection). This
design used s7-300PLC, which is produced Siemens', and PC used Wincc configuration
software, then design configuration environment of liquid mixing control system. Operators can
directly supervise and control condition of PLC, and they can change system’ parameters in the
Wincc so that improve the system efficiency.
Keywords ：Liquid mixture；Siemens S7-300；Programable Logic Controller ；Windows
Control Center
