The main use of PLC category

1. Switch quantity logic control

Replace the traditional relay circuit, complete the logic control, sequence control, can be used for single equipment control, can also be used for multi-machine group control and automated assembly line. Such as injection molding machines, printing presses, stapler machines, combined machine tools, beds, packaging production lines, electroplating lines, etc.

2. Industrial process control

In the industrial production process, there are some quantities such as temperature, pressure, flow, liquid level and speed that change continuously (that is, analog quantities), PLC uses the corresponding A/D and D/A conversion modules and a variety of control algorithms to deal with analog quantities and complete closed-loop control. PID adjustment is a kind of adjustment method used in general closed-loop control system. Process control is widely used in metallurgy, chemical industry, heat treatment, boiler control and other occasions.

3. Motion control

PLC can be used for circular or linear motion control. Generally use special motion control modules, such as single-axis or multi-axis azimuth control modules that can drive stepper motors or servo motors, widely used in various machinery, machine tools, robots, elevators and other occasions.

depict

With the development of PLC technology, its data storage area is getting larger and larger. For example, the PLC of Devison Company, its data storage area (DM area) can reach 9999 words. Such a huge data storage area

Large amounts of data can be stored. Data collection can use A counter to accumulate the number of pulses collected and transfer them to the DM area on time. Data collection can also be used as A/D unit. When the analog quantity is converted into a digital quantity, it can be transferred to the DM area on time. PLC can also be equipped with a small printer to regularly type out the data in the DM area.

PLC can also communicate with the computer, the data in the DM area is read out by the computer, and the data is processed by the computer. At this time, the PLC becomes the data terminal of the computer. Power users have used PLC to record the user’s electricity consumption in real time to complete the charging method of different electricity consumption times and different pricing, to encourage users to use more electricity when the electricity is low, and to achieve the intention of reasonable electricity consumption and saving electricity.

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