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You're reading from  Industrial Automation from Scratch

Product typeBook
Published inJun 2023
PublisherPackt
ISBN-139781800569386
Edition1st Edition
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Author (1)
Olushola Akande
Olushola Akande
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Olushola Akande

Olushola Akande is an industrial automation and robotics expert with over 10 years of experience in the design and development of automation and robotics-related projects. He is an industrial automation trainer and consultant with a passion for driving industries to achieve greater results by doing work more accurately with less effort of human control. He is the chief executive officer (CEO) of Showlight Technologies Limited, an industrial automation, robotics, artificial intelligence (AI), and machine learning (ML) training and servicing company in Lagos, Nigeria. He is a member of the Schneider Electric team involved in the installation of Integrated Control and Safety Systems (ICSSs), which includes high-integrity PLCs, supervisory control and data acquisition (SCADA) systems, and distributed control systems (DCSs) at the largest oil refinery in Africa (Dangote Oil Refinery) at Lekki Free Zone, Lagos, Nigeria.
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Understanding Human Machine Interfaces (HMIs)

The previous three chapters covered a great deal on Programmable Logic Controllers (PLCs), which are the brains behind most automated machines. We learned how to automate industrial processes using PLCs, sensors, and actuators. However, in most cases, PLCs, sensors, and actuators alone cannot give us the functionality required in a real-life industrial process. A Human Machine Interface (HMI) is usually integrated into a manufacturing line and other industrial processes to give users easy control of the machines and to give them feedback on machine statuses.

In the previous chapter, we learned how to control machines using PLCs, whereby the user or operator presses a push button to start the machine and a pilot light gives an indication of whether the machine is running or not. Integrating HMIs into such systems makes them more user-friendly. HMIs allow you to start or stop your machine and even get feedback or status updates for the...

Technical requirements

You will need an understanding of PLCs, sensors, and actuators from the previous three chapters.

Ensure you have downloaded and installed TIA Portal V13 on your PC or laptop. Please refer to Chapter 8, Understanding PLC Software and Programming with TIA Portal.

Other devices that may be required include Siemens HMI (KTP400) and Siemens PLC (S7 1200, CPU 1211C, AC/DC/RLY).

Introducing HMIs

HMIs can be seen as graphical interfaces that allow humans and machines to interact. We have learned that PLCs can control and automate industrial machines. HMIs, on the other hand, allow humans to interact or communicate with machines. No matter how we automate a process, we still need a human (an operator) to start or initiate the process, perform other functions, and get feedback on the machine’s operation.

HMIs allow humans to give commands to PLCs to control a process and also receive feedback from PLCs about the process. With HMIs, the human operator can interact with, monitor, and control machines via the PLC. The HMI is usually connected to the PLC via a communication cable, depending on the protocol being used (Ethernet/IP, Profinet, Profibus, or Modbus). This chapter does not discuss protocols. We will look into protocols in Chapter 13, Industrial Network and Communication Protocols Fundamentals. However, we will use Profinet as the protocol to...

Exploring the applications of HMIs

HMIs are used in almost all industries. Some industrial areas of application include the following:

  • Food and beverages: HMIs can be used to easily monitor and control production processes to ensure quality in the food and beverages industry. HMIs allow recipes to be used in production. “Recipes” simply refers to data or values that can be selected by a user depending on the type of product that is to be produced. Recipes summarize production data or machine configurations for a particular product. The data is then transferred from the HMI to the PLC or controller at a given time to switch production to another product type. Recipes are used when multiple products are to be produced. Recipes are not only advantageous in the food industry; they are also of great benefit in other industries that produce multiple products.
  • Oil and gas: HMIs provide a means by which drilling and rig operators can control and monitor their applications...

Understanding HMI programming and development

HMI programming involves the creation of the visual representation (graphic) of the machine operation, control commands, and writing codes to execute required functions.

The main purpose of an HMI is to allow the operator to control a machine or process. Hence, an HMI design must do the following:

  • Be easy for the user to have access to the necessary information and control.
  • Allow the user to navigate to different areas as quickly as possible.
  • Allow the user or operator to see the current status of the machine. The operator must be able to tell whether the machine is running or has stopped through visual indication on the HMI. Other information that can help the operator to make the right decision can also be provided.

Let’s proceed to learn about HMI programming software in the next section.

Understanding HMI programming software

HMI programming software is special software used for designing the graphical interface and writing some code where necessary for the interaction between the user (human) and the machine. The software is usually installed on the PC where programming will be done before it is downloaded to the HMI panel via a communication cable, just as we do for PLCs.

There are different kinds of programming software for different brands of HMI panels. The next section discusses various HMI manufacturers and their programming software.

Exploring HMI manufacturers and their programming software

Some of the popular HMI manufacturers are listed here:

  • Siemens: Siemens is a German company, one of the top companies in the automation industry, producing SIMATIC HMIs. Some of their HMI models include KTP400, KTP600, and KTP700. Their HMI programming software is WinCC.
  • Rockwell Automation: Rockwell Automation is one of the top companies in North America. Their HMI brand is called PanelView, which includes PanelView 600, Panel View 800, and PanelView+400. The programming software for their HMIs includes RSview32 and FactoryTalk View.
  • Schneider Electric: Schneider Electric is one of the top companies in Europe. Their HMI brands include Mangelis and Harmony. Their HMI programming and configuration software includes Ecostructure Operator Terminal Expert and Vijeo Designer.
  • Mitsubishi Electric Corporation: Mitsubishi Electric Corporation (MELCO) is a division of Mitsubishi. Their line of HMIs is called Graphical...

Interfacing PLCs and HMIs

In Chapter 9, Deep Dive into PLC Programming with TIA Portal, we learned how to use pushbuttons to start and stop and also how to use a lamp as an indicator that shows when a load is on or off.

As we discussed earlier, HMIs allows human operators to interact with machines via a PLC. This means that a PLC is required to communicate with the machine.

Here, in this section, we will learn how to interface a Siemens HMI (KTP 400) and a Siemens PLC using Profinet as a communication protocol. We will use TIA Portal to program the PLC and develop the HMI application using WinCC, which was installed when we installed TIA Portal in Chapter 8, Understanding PLC Software and Programming with TIA Portal.

By the end of this section, you should be able to interface PLCs and HMIs such that the HMI can be used to start and stop and get feedback on the status of a machine (for example, a motor).

We are already familiar with the Siemens S7 1200 PLC (CPU 1211C). The...

Downloading programs to PLCs and HMIs

Let's begin with downloading a program to a PLC (Siemens S7-1200). In Chapter 9, Deep Dive into PLC Programming with TIA Portal, we learned how to download programs to PLCs. We are going to do the same thing here:

  1. Connect an Ethernet cable to the PLC and PC as shown:
Figure 10.67 – Connection of PC (laptop) to PLC (S7 1200) using an Ethernet cable. (Credit for this image goes to Showlight Technologies LTD. www.showlight.com.ng)

Figure 10.67 – Connection of PC (laptop) to PLC (S7 1200) using an Ethernet cable. (Credit for this image goes to Showlight Technologies LTD. www.showlight.com.ng)

  1. At the left-hand side of the screen, expand the PLC folder, go to Program blocks, and double-click Main [0B1] to get your written program. Double-click Device configuration:
Figure 10.68 – Ladder logic program

Figure 10.68 – Ladder logic program

  1. Click Properties | General | PROFINET Interface [X1]:
Figure 10.69 – Device configuration (PLC_1)

Figure 10.69 – Device configuration (PLC_1)

  1. Scroll down and enter an IP address and an appropriate subnet mask...

Summary

Congratulations! You have successfully completed another chapter of this book. Good job! HMIs are used in conjunction with PLCs in various industries to give commands to machines and also to get feedback about a machine’s status. The hands-on/practical part of this chapter showed how HMIs, interfaced with PLCs, can be used to control a machine and also get feedback from a machine. This chapter also included simulation. You should be able to simulate your PLC and HMI programs even when you don’t have a real PLC and HMI panel to work with. The last section of this chapter explained how to download a program to a real PLC and HMI. Try to get your hands dirty with these tools.

In the next chapter, we will be learning about Supervisory Control and Data Acquisition (SCADA), which is another interesting topic that an industrial automation engineer needs to know about. Don’t miss it!

Questions

The following are questions to test your understanding of this chapter. Ensure you have read and understood the topics in this chapter before attempting the questions:

  1. HMI comprises both ______________ and ________________ that allow the communication between human operators and machines.
  2. MMI is an acronym for ___________________.
  3. OIT is an acronym for ________________.
  4. UI is an acronym for _____________.
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Published in: Jun 2023Publisher: PacktISBN-13: 9781800569386
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Author (1)

author image
Olushola Akande

Olushola Akande is an industrial automation and robotics expert with over 10 years of experience in the design and development of automation and robotics-related projects. He is an industrial automation trainer and consultant with a passion for driving industries to achieve greater results by doing work more accurately with less effort of human control. He is the chief executive officer (CEO) of Showlight Technologies Limited, an industrial automation, robotics, artificial intelligence (AI), and machine learning (ML) training and servicing company in Lagos, Nigeria. He is a member of the Schneider Electric team involved in the installation of Integrated Control and Safety Systems (ICSSs), which includes high-integrity PLCs, supervisory control and data acquisition (SCADA) systems, and distributed control systems (DCSs) at the largest oil refinery in Africa (Dangote Oil Refinery) at Lekki Free Zone, Lagos, Nigeria.
Read more about Olushola Akande