More than just start and stop

Article#: 00043

Date: 2020-12-10

Author: Radim

Machine program must be able to do more than just start and stop the machine.
Proper functionality, product quality, a useful user interface and the safety of people, the environment and equipment must be guaranteed.

Program must handle exceptional situations, deal with them and inform the operator accordingly.
It must guide the operator to resolve the problem when an intervention is required.
If something special happens, the program must not get lost in nirvana.
The program must expect the unexpected!
This can be, for example, an interruption in communication, a partial or complete power failure, an interruption of a function before its completion, a malfunction of sensors and actuators, another sequence of upcoming events, an operator failure, etc.

The straight forward way is only a small fraction of what the program must manage.
Each IF statement has at least one ELSE with it.
Interlocks of machine parts and machines must be implemented.
Alerting and instructing the operator to resolve the alarm situation must be implemented.
Self-remedy functions must be implemented.
Operator errors and their dangerous consequences must be avoided or limited.
...

What can the consequences be if a situation unexpected in the program occurs in reality?
Do you have any experience?

© Radim-Automation, 2020–2025. All rights reserved.
Sharing of this article is permitted with proper attribution (link to the original page).

Related previous articles:

• Safety first!
• Do the right things and do them right!
• Define test scenarios and test cases continuously!
• Don't make it worse!
• Write a project diary!
• Keep the answers to the question "Why"
• Everything is difficult until it becomes easy
• Realize every good idea ASAP!
• Industrial evolution - Listen to your customers and follow new trends!
• Stay alert!
• What does the customer need?
• Don't disappoint your customer!
• Ask questions!
• Focus on target!
• Don't hide any problem!
• Check the result!
• Keep it simple!
• Don't leave a work package half-finished!
• Success is not a matter of coincidence
• Development is evolution
• Don't neglect and don't skip any step!
• Transparency and reliability
• From an idea to a consistent system

Related next articles:

• I can see what you can not see
• Do you really want to start with this?
• Is the way really the goal?
• Prepare a good project plan and keep it up to date!
• HMI and PLC applications should grow together
• Write and accept only readable code!
• Functional and intuitive HMI
• Who will operate?
• Collect all the requirements and sort them!
• Why do automation projects fail?
• Project leader
• Learn from your journey!
• Think critically!
• Are there also any disadvantages?
• A good concept = Complete set of suitable solutions
• Hardware concept
• Modular software architecture
• Abbreviations
• Machine modularization
• Knowledge gained from a completed project is priceless
• Variable names
• Choice of programming language
• Visual modeling
• Safety relays versus safety PLC
• Software update
• Design considerations for effective HMIS
• Clear signals
• Talk to operators
• It doesn't work without sensors
• Event logger as the very first function implemented in the program
• Diagnostic tools
• My boss was a hero
• Version control system
• PLC network diagram
• Maintain order in the program code
• Make backups, make small changes and test a lot
• Graphic designer
• Dream of a platform-independent PLC program
• High Performance HMI
• An irreplaceable employee
• HMI - Have a consistent style
• HMI - Don't overdo it with complex design
• Hidden dangers during commissioning
• HMI is not a web page
• Choosing an HMI display
• The false illusion of rapid progress
• HMI layout and correct display size
• HMI layout design
• HMI navigation
• HMI - back and forward navigation buttons
• HMI – Don’t hide anything
• HMI - annoying pop-up windows
• HMI - colors in the visualization

Comment#: 00001

Date: 2021-09-10

User: Radim

Does the user not know why the system is not doing what it is supposed to? This is not the user's fault, but the system's creator!
The system must inform and guide the user step by step both during normal operation and during troubleshooting.

Comment#: 00002

Date: 2021-10-04

User: Radim

It is important to build such a system so that it is easy to find out why something is not working when something is not working.

Comment#: 00003

Date: 2022-06-20

User: Radim

What is actually the core of automation?
"As the word suggests, the core of industrial automation is that processes run automatically, i.e. without human intervention. The challenge here is reliability. That means automating something in such a way that people have to help out with every small problem – that is not in the sense of real automation. Only when the automation works safely in terms of plant safety and reliably in terms of continuous availability can one speak of real industrial automation."
- Dr. Henning Grönzin
- https://www.elektrotechnik.vogel.de/was-eigentlich-ist-der-kern-der-automatisierung-a-e4da2bbaa2d8839077a1644e177599c0/?p=4

Comment#: 00004

Date: 2022-09-22

User: Radim

"In addition to streamlined development and commissioning, another hallmark of an intelligent machine is that maintenance can be performed quickly and easily. In the event of a malfunction, service technicians need to locate the problem and contact the machine builder as quickly as possible."
- www.br-automation.com/en/about-us/press-room/technology-highlights/together-at-last/

Comment#: 00005

Date: 2022-10-31

User: Radim

"Disciplined testing and commissioning procedures executed by qualified resources are critical for safe and efficient startup. Shortcuts here inevitably lead to ongoing operational problems, costing many times the minimal savings from reduced commissioning time."
- https://blog.isa.org/industrial-automation-projects-challenging-management

Comment#: 00006

Date: 2023-04-10

User: Radim

Special care should be taken before setting a breakpoint in a program on a real machine. Especially if the program is responsible for controlling and stopping drives and processes.
Hitting a breakpoint stops the entire application running on the target system. However, the states of the outputs of I/O modules remain unchanged!
Running drives and started processes are not stopped and keep running when the application stops at a breakpoint. And no one has control over them anymore!
In a properly designed system, an independent safety function must stop running drives and processes at the latest before a collision occurs.

Comment#: 00007

Date: 2023-07-11

User: Radim

"New risks are also emerging in automated production, because who will restart a plant or even just a machine if the staff responsible for it at the time of shutdown are no longer working in the same plant. The transfer of knowledge, for example about the last software versions or settings, becomes indispensable. If you do not have the processes and the right solution in place, you risk everything. At this point, trends such as deploying increasing amounts of robots can only help to a limited extent, because even robots are dependent on updates and a certain level of maintenance."
- Curated by Statista, supported by octoplant by AUVESY-MDT. No Fatalism in Manufacturing. Exciting Insights from Leading Studies. (Page 5)
- https://info.auvesy-mdt.com/hubfs/Statista%20ePaper%20EN%20-%20AUVESY-MDT.pdf

Comment#: 00009

Date: 2023-07-14

User: Radim

"A good interface is easy to learn, leads to faster reaction time, safer operations and higher productivity. You deserve a system that is intuitive - one that at a glance you can see what actions need to be taken and is easy to navigate."
- General Electric (2021). Modern HMI/SCADA Guidebook for Efficient Operations.
- https://www.ge.com/digital/lp/modern-hmiscada-guidebook-efficient-operations

Comment#: 00010

Date: 2023-07-21

User: Radim

"The essential function of the PLC is to receive data from sensors or other field devices; make a decision on what to do with that information based on its programming instructions, for example, to open or close a valve based on fluid levels or direct a robot to pick up an object based on its presence in the work cell; and send the correct signal to the actuator (such as a valve or robot gripper) to perform the task."
- David Greenfield. AutomationWorld (2023). Peer-to-Peer FAQ: Controllers.
- https://www.automationworld.com/control/article/22724233/industrial-controller-technologies

Comment#: 00011

Date: 2023-08-10

User: Radim

"The information that should be available on a graphical user interface (GUI) of a machine depends heavily on the type of machine and its application. However, here are some basic pieces of information that are often displayed on a GUI:

1. Status Information: The GUI should display important status information about the machine, such as whether it's powered on or operational, whether it has issues or error messages, and whether all systems are functioning properly.

2. Operational Parameters: Display the current operational parameters of the machine, such as speed, temperature, pressure, voltage, etc. This allows the user to monitor the machine's current state and make adjustments if needed.

3. Process Overview: If the machine is involved in an ongoing process (e.g., manufacturing, processing, analysis), relevant process data and steps should be displayed on the GUI. This helps the operator monitor the progress of the process and identify potential deviations.

4. Warnings and Error Messages: Display warnings or error messages if problems or critical situations arise. This enables the operator to react quickly and take appropriate actions.

5. User Interaction: Provide interfaces for user interaction, such as adjusting settings, changing parameters, or issuing commands. This includes buttons, dropdown menus, text fields, and other elements.

6. Historical Data: A history or log of past events and activities can be helpful for identifying trends, diagnosing errors, or making performance improvements.

7. Documentation and Help Material: Provide user manuals, help tutorials, or links to further information so that users can learn about operation, maintenance, and potential issue resolutions.

8. Visualizations: Depending on the application, charts, graphs, or visual representations of relevant data can be useful for recognizing relationships and trends more easily.

9. User Profiles and Settings: Allow users to create individual profiles and configure specific settings to match their workflow.

10. Safety Information: If the machine could potentially be hazardous, the GUI should display safety instructions, emergency stop buttons, or other safety mechanisms.

11. Contact Information and Support: Provide contact information for technical support or customer service in case users need assistance or support.

It's important to carefully design the GUI based on user needs and the type of machine to ensure a user-friendly and efficient experience."

- https://chat.openai.com (What information should be available in the machine's graphical user interface?)

Comment#: 00013

Date: 2023-08-18

User: Radim

"Don't dig deep into anything because it costs us money. Just pretend that we are experts and hope that the others gets the chestnuts out of the fire."
- unnamed user (own experiences leading to this ironic statement)

Comment#: 00014

Date: 2023-09-11

User: Radim

Does it make sense to think about digitalization if we don't see any use case?

"If you don't see any practical use case or clear benefit for digitalization in your specific situation, it may not make sense to pursue it blindly. Digitalization should always align with your organization's goals and needs. Here are some considerations:

1. Assess Business Objectives: Start by identifying your organization's objectives and challenges. Digitalization should align with your strategic goals, whether it's improving efficiency, reaching new markets, enhancing customer experiences, or reducing costs.

2. Customer Demands: Consider whether your customers or clients expect or would benefit from digital solutions. If there's no demand for digital services, investing in them may not provide a return on investment.

3. Competitive Landscape: Analyze your competition. If your competitors are effectively utilizing digital technologies to gain a competitive advantage, it might be necessary to explore digitalization to stay relevant.

4. Cost-Benefit Analysis: Conduct a thorough cost-benefit analysis to determine if the potential benefits of digitalization outweigh the costs. If the investment doesn't offer a reasonable return, it might not be justified.

5. Resource Availability: Evaluate whether you have the necessary resources, including financial resources, technical expertise, and staff training, to implement and sustain digital solutions effectively.

6. Future Growth: Consider the scalability of your organization. Even if you don't currently see a clear use case for digitalization, it's essential to think about your organization's future growth and whether digital technologies could play a role in that growth.

7. Technology Trends: Stay informed about industry trends and emerging technologies. While there may not be an immediate use case, technological advancements could create new opportunities down the line.

8. Customer Feedback: Engage with your customers or stakeholders to gather feedback on their needs and preferences. They may provide insights that could uncover potential use cases for digitalization.

9. Pilot Projects: Instead of a full-scale digital transformation, consider starting with smaller pilot projects to test the waters and assess the feasibility and impact of digital solutions in a controlled environment.

10. Consult Experts: Seek advice from digital transformation consultants or experts in your industry. They can provide insights into potential use cases and help you determine if digitalization is appropriate for your organization.

In some cases, it may indeed be the case that digitalization doesn't make sense for your organization at a given time. However, it's essential to regularly revisit this assessment as technology and business landscapes evolve. What might not be relevant today could become essential in the future. Ultimately, the decision to pursue digitalization should be guided by a thorough understanding of your organization's unique needs and circumstances."

- https://chat.openai.com (Does it make sense to think about digitalization if we don't see any use case?)

Comment#: 00015

Date: 2023-09-15

User: Radim

Complaints and identified problems are good sources of innovation.

Comment#: 00016

Date: 2023-09-27

User: Radim

"By continuously improving the design of code, we make it easier and easier to work with.
This is in sharp contrast to what typically happens: little refactoring and a great deal of attention paid to expediently add new features.
If you get into the hygienic habit of refactoring continuously, you'll find that it is easier to extend and maintain code."

- Joshua Kerievsky. Addison-Wesley (2004). Refactoring to Patterns.

Comment#: 00017

Date: 2023-10-04

User: Radim

"Never discourage anyone who continually makes progress, no matter how slow."
- Plato

Comment#: 00020

Date: 2024-02-14

User: Radim

Benefits and risks of software updates via remote access to customer machines

In today's agile world, quick and easy software updates are essential for maintaining technologies and systems. However, the transition from manual installation of updates to remote access raises an important discussion about the risks and benefits of this approach.

Technical feasibility and tools:
The technical aspect is not an obstacle. With today's concepts and tools, the application software can be updated on remote machines at the customer's premises.

Risks:
However, the main concerns relate to the risks associated with this procedure. There is a possibility that the installation of the new software version may cause unexpected problems that can have serious consequences. The machine may no longer be able to be started and may even no longer be accessible remotely. A specialist then has to travel to the customer. This can take up to several days and leads to expensive production downtime for the customer.

Benefits:
Conversely, remote software updates have many advantages. Customers do not have to wait for a technician to be present, which saves time and travel costs. In addition, the rapid availability of updates can improve overall customer satisfaction and increase efficiency.

Solution:
To minimize the risks associated with remote updates, clear rules and procedures must be established. These include thorough testing of updates prior to deployment, detailed data backup and recovery plans and adequate training of customer personnel.

Comment#: 00021

Date: 2024-07-03

User: Radim

Bear in mind that the operator sometimes operates the system in a panic and needs a short and fast route to the destination and a quick response from the system. The system must inform the operator of what has happened and what is expected of the operator.