Introduction to Industrial Automation

Figure 1.2  Simplified visualization of the pulp processing stages.

Figure 1.1  Schematic of a pulp and paper industrial process.

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Industrial Automation 

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Before analyzing the procedures needed for automating an industrial production line, it is of 

paramount importance to initially define in detail the various components that the automation 

and their specific functionalities and properties consist of. In an industrial production line, the 

“movement” is the fundamental and generalized characteristic of the overall process, since it is 

impossible to consider an industrial process without the existence of a linear, circular, or any other 

form of movement. Even in the case of a chemical reaction, where the existence of motion is not 

obvious, the movement also exists in this case and more specifically in the form of an electrovalve 

control, which opens in order to supply the reactor with the necessary amount of the reacted 

components. Furthermore, the existence of the need for movement is significantly evident, either in 

the cases where the product should be transferred to the various process points of the production 

line, or in the cases of integrated machines, where parts of the machines should be moved in order 

to produce the desired processing of the developing product. The machines that can be utilized for 

the creation of the movement can be categorized into two large categories, as displayed in Figure 1.3.

The first category includes the different types of motors, independently of the operating principle 

(e.g., one-phase motors, three-phase motors, motors with short-circuit rotors, motors with direct 

start, motors that start in a Y/

Δ

 mode, etc.) that creates a primary rotational movement, which 

can be further transformed by the utilization of appropriate mechanisms in a linear or other type 

of movements. The second category includes all the actuators, where a linear movement is created 

as the result of the attraction generated by an electromagnet (coil) on a ferromagnetic core, such 

as the various forms of electro-vanes, electrovalves, etc. The common characteristic of motors and 

actuators is the fact that they have only two possible states of operation. For expressing these states, 

Actuators

(On-Off)

(On-Off)

(On-Off)

(On-Off)

(On-Off)

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end

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nc

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I

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pe

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Sensors

Continuous

control unit

R +

–

E

B

G

H

C

c(t)

r(t)

Indicators

Handling

devices

Motors